diff --git a/Package.swift b/Package.swift
index 890f5f4..5311008 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,7 +1,7 @@
 import PackageDescription
 import Foundation
 
-var repos = ["Perfect-Crypto"]
+var repos = ["Perfect-HTTPServer"]
 var targets = [Target(name: "PerfectSSOAuth", dependencies: [])]
 let excludes: [String]
 let db: String
diff --git a/README.md b/README.md
index b047e3c..befc2d1 100644
--- a/README.md
+++ b/README.md
@@ -249,7 +249,7 @@ Certainly, you can skip the log system if no need, which will log to the console
 let man = LoginManager<Profile>(udb: udb)
 ```
 
-Now you can use the `LoginManager` instance to register, login, load profile, update password and update profile, or drop users: 
+Now you can use the `LoginManager` instance to register, login, load profile, update password and update profile, or drop user:
 
 #### Register & Login
 
@@ -264,6 +264,8 @@ let token = try man.login(id: "someone", password: "secret")
 **NOTE**: By default, both user id and password are in a length of **[5,80]** string. 
 Check [Login / Password Quality Control](#login--password-quality-control) for more information.
 
+**NOTE** For those end users who want user id to be an autoincrement UInt64 id, please fork this repo to make your own edition.
+
 The token generated by `LoginManager.login()` is a JWT for HTTP web servers.
 
 It is supposed to send to the client (browser) as a proof of authentication.
diff --git a/README.zh_CN.md b/README.zh_CN.md
index b54084b..e65cad1 100644
--- a/README.zh_CN.md
+++ b/README.zh_CN.md
@@ -259,6 +259,8 @@ let token = try man.login(id: "someone", password: "secret")
 **注意**: 默认状态下用户名密码长度都是 **[5,80]** 之间的字符串。
 详见 [用户名密码质量控制](#login--password-quality-control)。
 
+**注意** 如果最终用户希望用可以自动递增的UInt64作为用户id，请自行创建本项目分支版本进行调整。
+
 调用 `LoginManager.login()` 登录后产生的令牌是一个JWT字符串，可以用于HTTP服务器进行权鉴认证。
 
 该令牌应该送回给客户端（浏览器）用于后续安全会话的权限凭证。
diff --git a/Sources/PerfectSSOAuth/DataworkUtility.swift b/Sources/PerfectSSOAuth/DataworkUtility.swift
index b246b17..356a312 100644
--- a/Sources/PerfectSSOAuth/DataworkUtility.swift
+++ b/Sources/PerfectSSOAuth/DataworkUtility.swift
@@ -8,6 +8,48 @@ public enum Exception: Error {
 
   /// an error with a readable reason.
   case fault(String)
+
+  /// something about json
+  case json
+
+  /// bad user name
+  case username
+
+  /// bad password
+  case password
+
+  /// encryption failure
+  case encryption
+
+  /// digestion failure
+  case digestion
+
+  /// access denied
+  case access
+
+  /// bad format
+  case malformed
+
+  /// bad request
+  case request
+
+  /// expired
+  case expired
+
+  /// violation
+  case violation
+
+  /// record not found
+  case inexisting
+
+  /// operation failure
+  case operation
+
+  /// unsupported
+  case unsupported
+
+  /// connection failure
+  case connection
 }
 
 /// a log file record
@@ -148,7 +190,7 @@ public final class DataworkUtility {
     guard let json = String.init(bytes: data, encoding: .utf8),
       let payload = try json.jsonDecode() as? [String:Any]
       else {
-        throw Exception.fault("json decoding failure")
+        throw Exception.json
     }
     var result:[Field] = []
     for (key, value) in payload {
diff --git a/Sources/PerfectSSOAuth/PerfectSSOAuth.swift b/Sources/PerfectSSOAuth/PerfectSSOAuth.swift
index bb2e878..e61f39f 100644
--- a/Sources/PerfectSSOAuth/PerfectSSOAuth.swift
+++ b/Sources/PerfectSSOAuth/PerfectSSOAuth.swift
@@ -1,5 +1,7 @@
 import PerfectLib
 import PerfectCrypto
+import PerfectHTTP
+import PerfectHTTPServer
 import Foundation
 import Dispatch
 
@@ -202,12 +204,12 @@ public final class HumblestLoginControl: LoginQualityControl {
   }
   public func goodEnough(userId: String) throws {
     guard userId.count.inRange(of: size) else {
-      throw Exception.fault("invalid username")
+      throw Exception.username
     }
   }
   public func goodEnough(password: String) throws {
     guard password.count.inRange(of: size) else {
-      throw Exception.fault("invalid password")
+      throw Exception.password
     }
   }
 }
@@ -260,7 +262,7 @@ public class LoginManager<Profile> where Profile: Codable {
   /// - throws: Exception.
   fileprivate func shadow(_ password: String, salt: String) throws -> String? {
     guard let hashData = salt.digest(.sha384) else {
-      throw Exception.fault("digest(sha384)")
+      throw Exception.digestion
     }
     let hashKeyData:[UInt8] = hashData[0..<32].map {$0}
     let ivData:[UInt8] = hashData[32..<48].map {$0}
@@ -268,7 +270,7 @@ public class LoginManager<Profile> where Profile: Codable {
     guard let x = data.encrypt(self._cipher, key: hashKeyData, iv: ivData),
       let y = x.encode(.base64)
       else {
-        throw Exception.fault("aes(128)+base64")
+        throw Exception.encryption
     }
     return String(validatingUTF8: y)
   }
@@ -335,9 +337,9 @@ public class LoginManager<Profile> where Profile: Codable {
       try _rate.onAttemptRegister(id, password: password)
       try _pass.goodEnough(userId: id)
       try _pass.goodEnough(password: password)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .registration, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .registration, message: error.localizedDescription)
+      throw error
     }
     guard let random = ([UInt8](randomCount: _saltLength)).encode(.hex),
       let salt = String(validatingUTF8: random),
@@ -345,17 +347,17 @@ public class LoginManager<Profile> where Profile: Codable {
       else {
         _log.report(id, level: .critical, event: .registration,
                     message: "unable to register '\(id)'/'\(password)' because of encryption failure")
-        throw Exception.fault("crypto failure")
+        throw Exception.encryption
     }
     let u = UserRecord<Profile>(id: id, salt: salt, shadow: shadow, profile: profile)
     _lock.wait()
     do {
       try _insert(u)
       _lock.signal()
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .registration, message: err.localizedDescription)
+    } catch {
+      _log.report(id, level: .warning, event: .registration, message: error.localizedDescription)
       _lock.signal()
-      throw err
+      throw error
     }
     _log.report(id, level: .event, event: .registration, message: "user registered")
   }
@@ -370,9 +372,9 @@ public class LoginManager<Profile> where Profile: Codable {
       try _rate.onUpdate(id, password: password)
       try _pass.goodEnough(userId: id)
       try _pass.goodEnough(password: password)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .updating, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .updating, message: error.localizedDescription)
+      throw error
     }
     guard let random = ([UInt8](randomCount: _saltLength)).encode(.hex),
       let salt = String(validatingUTF8: random),
@@ -380,7 +382,7 @@ public class LoginManager<Profile> where Profile: Codable {
       else {
         _log.report("unknown", level: .warning, event: .updating,
                     message: "invalid update attempt '\(id)'/'\(password)'")
-        throw Exception.fault("crypto failure")
+        throw Exception.encryption
     }
     do {
       _lock.wait()
@@ -389,10 +391,10 @@ public class LoginManager<Profile> where Profile: Codable {
       u.shadow = shadow
       try self._update(u)
       _lock.signal()
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .updating, message: err.localizedDescription)
+    } catch {
+      _log.report(id, level: .warning, event: .updating, message: error.localizedDescription)
       _lock.signal()
-      throw err
+      throw error
     }
     _log.report(id, level: .event, event: .updating, message: "password updated")
   }
@@ -405,9 +407,9 @@ public class LoginManager<Profile> where Profile: Codable {
   public func update(id: String, profile: Profile) throws {
     do {
       try _pass.goodEnough(userId: id)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .updating, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .updating, message: error.localizedDescription)
+      throw error
     }
     do {
       _lock.wait()
@@ -418,10 +420,10 @@ public class LoginManager<Profile> where Profile: Codable {
       _lock.wait()
       try self._update(u)
       _lock.signal()
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .updating, message: err.localizedDescription)
+    } catch {
+      _log.report(id, level: .warning, event: .updating, message: error.localizedDescription)
       _lock.signal()
-      throw err
+      throw error
     }
     _log.report(id, level: .event, event: .updating, message: "profile updated")
   }
@@ -442,9 +444,9 @@ public class LoginManager<Profile> where Profile: Codable {
       try _pass.goodEnough(userId: id)
       try _pass.goodEnough(password: password)
       try _rate.onAttemptLogin(id, password: password)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .login, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .login, message: error.localizedDescription)
+      throw error
     }
     let u: U
     do {
@@ -452,10 +454,10 @@ public class LoginManager<Profile> where Profile: Codable {
       u = try _select(id)
       _lock.signal()
       try _rate.onLogin(u)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .login, message: err.localizedDescription)
+    } catch {
+      _log.report(id, level: .warning, event: .login, message: error.localizedDescription)
       _lock.signal()
-      throw err
+      throw error
     }
     guard
       let shadow = try self.shadow(password, salt: u.salt),
@@ -463,7 +465,7 @@ public class LoginManager<Profile> where Profile: Codable {
       else {
         _log.report(id, level: .warning, event: .login,
                     message: "access denied")
-        throw Exception.fault("access denied")
+        throw Exception.access
     }
     return try self.renew(u: u, subject: subject, timeout: timeout, headers: headers)
   }
@@ -481,24 +483,24 @@ public class LoginManager<Profile> where Profile: Codable {
     (header: [String: Any], content: [String: Any]) {
     do {
       try _rate.onAttemptToken(token: token)
-    } catch (let err) {
-      _log.report("unknown", level: .warning, event: .verification, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report("unknown", level: .warning, event: .verification, message: error.localizedDescription)
+      throw error
     }
     guard let jwt = JWTVerifier(token),
       let id = jwt.payload["aud"] as? String else {
       _log.report("unknown", level: .warning, event: .verification,
                   message: "jwt verification failure")
-      throw Exception.fault("jwt verification failure")
+      throw Exception.access
     }
     let u: U
     do {
       _lock.wait()
       u = try _select(id)
       _lock.signal()
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .verification, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .verification, message: error.localizedDescription)
+      throw error
     }
     let now = time(nil)
     do {
@@ -506,14 +508,14 @@ public class LoginManager<Profile> where Profile: Codable {
     } catch {
       _log.report(id, level: .warning, event: .verification,
                   message: "jwt verification failure: \(token)")
-      throw Exception.fault("jwt verification failure")
+      throw Exception.access
     }
     guard let iss = jwt.payload["iss"] as? String else {
-      throw Exception.fault("issuer is null")
+      throw Exception.malformed
     }
     if iss != _managerID {
       guard allowSSO else {
-        throw Exception.fault("invalid issuer")
+        throw Exception.malformed
       }
     }
     guard let timeout = jwt.payload["exp"] as? Int,
@@ -524,7 +526,7 @@ public class LoginManager<Profile> where Profile: Codable {
       else {
         _log.report(id, level: .warning, event: .verification,
                     message: "jwt invalid payload: \(jwt.payload)")
-        throw Exception.fault("token failure")
+        throw Exception.malformed
     }
 
     _lock.wait()
@@ -533,7 +535,7 @@ public class LoginManager<Profile> where Profile: Codable {
 
     if rejected {
       _log.report(id, level: .warning, event: .verification, message: "rejected")
-      throw Exception.fault("rejected")
+      throw Exception.access
     }
 
     if logout {
@@ -541,11 +543,11 @@ public class LoginManager<Profile> where Profile: Codable {
         _lock.wait()
         try _ban(ticket, timeout)
         _lock.signal()
-      } catch (let err) {
+      } catch {
         _log.report(id, level: .warning, event: .logoff,
-                    message: "log out failure:" + err.localizedDescription )
+                    message: "log out failure:" + error.localizedDescription )
         _lock.signal()
-        throw err
+        throw error
       }
     }
     return (header: jwt.header, content: jwt.payload)
@@ -565,16 +567,16 @@ public class LoginManager<Profile> where Profile: Codable {
     guard let jwt = JWTCreator(payload: claims) else {
       _log.report(u.id, level: .critical, event: .login,
                   message: "token failure")
-      throw Exception.fault("token failure")
+      throw Exception.malformed
     }
 
     let ret: String
     do {
       ret = try jwt.sign(alg: _alg, key: u.salt, headers: headers)
-    } catch (let err) {
+    } catch {
       _log.report(u.id, level: .critical, event: .login,
-                  message: "jwt signature failure: \(err)")
-      throw err
+                  message: "jwt signature failure: \(error.localizedDescription)")
+      throw error
     }
     _log.report(u.id, level: .event, event: .login, message: "user logged")
     return ret
@@ -594,9 +596,9 @@ public class LoginManager<Profile> where Profile: Codable {
                     headers: [String:Any] = [:]) throws -> String {
     do {
       try _pass.goodEnough(userId: id)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .renewal, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .renewal, message: error.localizedDescription)
+      throw error
     }
     let u: U
     do {
@@ -604,9 +606,9 @@ public class LoginManager<Profile> where Profile: Codable {
       u = try _select(id)
       _lock.signal()
       try _rate.onRenewToken(u)
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .renewal, message: err.localizedDescription)
-      throw err
+    } catch {
+      _log.report(id, level: .warning, event: .renewal, message: error.localizedDescription)
+      throw error
     }
     return try self.renew(u: u, subject: subject, timeout: timeout, headers: headers)
   }
@@ -638,12 +640,205 @@ public class LoginManager<Profile> where Profile: Codable {
       try _delete(id)
       _lock.signal()
       _log.report(id, level: .event, event: .unregistration, message: "user closed")
-    } catch (let err) {
-      _log.report(id, level: .warning, event: .unregistration, message: err.localizedDescription)
+    } catch {
+      _log.report(id, level: .warning, event: .unregistration, message: error.localizedDescription)
       _lock.signal()
-      throw err
+      throw error
     }
   }
 }
 
 
+public class HTTPAccessControl<Profile>: HTTPRequestFilter where Profile:Codable {
+
+  public func filter(request: HTTPRequest, response: HTTPResponse,
+                     callback: (HTTPRequestFilterResult) -> ()) {
+
+    do {
+      switch request.uri {
+      case _config.reg:
+        let cookie = try self.register(request: request)
+        response.addCookie(cookie)
+        break
+      case _config.login:
+        let cookie = try self.login(request: request)
+        response.addCookie(cookie)
+        break
+      case _config.logout:
+        try self.logout(request: request)
+        break
+      case _config.modpass:
+        try self.modpass(request: request)
+        break
+      case _config.update:
+        try self.update(request: request)
+        break
+      case _config.drop:
+        try self.drop(request: request)
+        break
+      default:
+        let (id, profile) = try self.access(request: request)
+        response.request.scratchPad["id"] = id
+        response.request.scratchPad["profile"] = profile
+        callback(.continue(request, response))
+        return
+      }
+      response.setHeader(.contentType, value: "text/json")
+      response.setBody(string: "{\"error\":\"\"}")
+      response.completed()
+      callback(.execute(request, response))
+    } catch {
+      response.setHeader(.contentType, value: "text/json")
+      response.setBody(string: "{\"error\":\"\(error.localizedDescription)\"}")
+      response.completed()
+      callback(.halt(request, response))
+    }
+  }
+
+  public struct Configuration: Codable {
+
+    /// URIs / routes
+    public var reg = "/api/reg"
+    public var login = "/api/login"
+    public var logout = "/api/logout"
+    public var update = "/api/update"
+    public var modpass = "/api/modpass"
+    public var drop = "/api/drop"
+
+    /// variables
+    public var id = "id"
+    public var password = "password"
+    public var profile = "profile"
+    public var jwt = "jwt"
+    public var aud = "aud"
+  }
+
+  let _man: LoginManager<Profile>
+  let _config: Configuration
+  let _encoder: JSONEncoder
+  let _decoder: JSONDecoder
+
+  public init(_ manager: LoginManager<Profile>, configuration: Configuration) {
+    _man = manager
+    _config = configuration
+    _encoder = JSONEncoder()
+    _decoder = JSONDecoder()
+  }
+
+  internal func profile(of: String) throws -> Profile {
+    let bytes: [UInt8] = of.utf8.map { $0 }
+    let data = Data.init(bytes: bytes)
+    return try _decoder.decode(Profile.self, from: data)
+  }
+
+  public func register(request: HTTPRequest) throws -> PerfectHTTP.HTTPCookie {
+    guard
+      request.uri == _config.reg,
+      let id = request.param(name: _config.id),
+      let password = request.param(name: _config.password),
+      let json = request.param(name: _config.profile)
+      else {
+        throw Exception.request
+    }
+    try _man.register(id: id, password: password, profile: try profile(of: json))
+    return try login(id: id, password: password)
+  }
+
+  public func login(request: HTTPRequest) throws -> PerfectHTTP.HTTPCookie {
+    guard request.uri == _config.login,
+      let id = request.param(name: _config.id),
+      let password = request.param(name: _config.password)
+      else {
+        throw Exception.request
+    }
+    return try login(id: id, password: password)
+  }
+
+  internal func login(id: String, password: String) throws -> PerfectHTTP.HTTPCookie {
+    let token = try _man.login(id: id, password: password)
+    return HTTPCookie(
+      name: _config.jwt,
+      value: token,
+      domain: "",
+      expires: .relativeSeconds(600),
+      path: "/",
+      secure: false,
+      httpOnly: true,
+      sameSite: .strict
+    )
+  }
+
+  public func jwt(of: HTTPRequest) -> String? {
+    var token = ""
+    for (k, v) in of.cookies {
+      if k == _config.jwt {
+        token = v
+      }
+    }
+    if token.isEmpty { return nil }
+    return token
+  }
+
+  public func update(request: HTTPRequest) throws {
+    guard request.uri == _config.update,
+      let token = jwt(of: request),
+      let json = request.param(name: _config.profile)
+      else {
+        throw Exception.request
+    }
+    let (_, content) = try _man.verify(token: token)
+    guard let id = content[_config.aud] as? String else {
+      throw Exception.malformed
+    }
+    let p = try profile(of: json)
+    try _man.update(id: id, profile: p)
+  }
+
+  public func modpass(request: HTTPRequest) throws {
+    guard request.uri == _config.modpass,
+      let token = jwt(of: request),
+      let newpass = request.param(name: _config.password)
+      else {
+        throw Exception.request
+    }
+    let (_, content) = try _man.verify(token: token)
+    guard let id = content[_config.aud] as? String else {
+      throw Exception.malformed
+    }
+    try _man.update(id: id, password: newpass)
+  }
+
+  public func access(request: HTTPRequest) throws -> (String,Profile) {
+    guard let token = jwt(of: request)
+      else {
+        throw Exception.request
+    }
+    let (_, content) = try _man.verify(token: token)
+    guard let id = content[_config.aud] as? String else {
+      throw Exception.malformed
+    }
+    let p = try _man.load(id: id)
+    return (id, p)
+  }
+
+  public func logout(request: HTTPRequest) throws {
+    guard request.uri == _config.logout,
+      let token = jwt(of: request)
+      else {
+        throw Exception.request
+    }
+    _ = try _man.verify(token: token, logout: true)
+  }
+
+  public func drop(request: HTTPRequest) throws {
+    guard request.uri == _config.drop,
+      let token = jwt(of: request) else {
+        throw Exception.request
+    }
+    let (_, content) = try _man.verify(token: token)
+    guard let id = content[_config.aud] as? String else {
+      throw Exception.malformed
+    }
+    _ = try _man.drop(id: id)
+  }
+}
diff --git a/Sources/UDBJSONFile/UDBJSONFile.swift b/Sources/UDBJSONFile/UDBJSONFile.swift
index 6420bc1..06b0243 100644
--- a/Sources/UDBJSONFile/UDBJSONFile.swift
+++ b/Sources/UDBJSONFile/UDBJSONFile.swift
@@ -31,7 +31,7 @@ public class UDBJSONFile<Profile>: UserDatabase {
 
   public func ban(_ ticket: String, _ expiration: time_t) throws {
     guard expiration > time(nil) else {
-      throw Exception.fault("ticket has already expired")
+      throw Exception.expired
     }
     self.autoflush()
     tickets[ticket] = expiration
@@ -68,14 +68,14 @@ public class UDBJSONFile<Profile>: UserDatabase {
   public func insert<Profile>(_ record: UserRecord<Profile>) throws {
     let data = try encoder.encode(record)
     if 0 == access(path(of: record.id), 0) {
-      throw Exception.fault("record has already registered")
+      throw Exception.violation
     }
     try data.write(to: self.url(of: record.id))
   }
 
   public func select<Profile>(_ id: String) throws -> UserRecord<Profile> {
     guard 0 == access(path(of: id), 0) else {
-      throw Exception.fault("record does not exist")
+      throw Exception.inexisting
     }
     let data = try Data(contentsOf: url(of: id))
     return try decoder.decode(UserRecord.self, from: data)
@@ -84,14 +84,14 @@ public class UDBJSONFile<Profile>: UserDatabase {
   public func update<Profile>(_ record: UserRecord<Profile>) throws {
     let data = try encoder.encode(record)
     guard 0 == access(path(of: record.id), 0) else {
-      throw Exception.fault("record does not exist")
+      throw Exception.inexisting
     }
     try data.write(to: url(of: record.id))
   }
 
   public func delete(_ id: String) throws {
     guard 0 == unlink(path(of: id)) else {
-      throw Exception.fault("operation failure")
+      throw Exception.operation
     }
   }
 
@@ -101,7 +101,7 @@ public class UDBJSONFile<Profile>: UserDatabase {
       closedir(dir)
     } else if autocreation {
       guard 0 == mkdir(directory, mode_t(permission)) else {
-        throw Exception.fault("operation failure")
+        throw Exception.operation
       }
     }
     touch = time(nil)
diff --git a/Sources/UDBMariaDB/UDBMariaDB.swift b/Sources/UDBMariaDB/UDBMariaDB.swift
index 318dd42..4b83b3c 100644
--- a/Sources/UDBMariaDB/UDBMariaDB.swift
+++ b/Sources/UDBMariaDB/UDBMariaDB.swift
@@ -18,8 +18,8 @@ extension MySQLStmt {
     } else if x is [Int8], let y = x as? [Int8] {
       self.bindParam(y, length: y.count)
     } else {
-      let tp = type(of: x)
-      throw Exception.fault("incompatible type: \(tp)")
+      //let tp = type(of: x)
+      throw Exception.unsupported
     }
   }
 }
@@ -38,7 +38,7 @@ public class UDBMariaDB<Profile>: UserDatabase {
       touch = now
     }
   }
-  
+
   public init<Profile: Codable>
     (host: String, user: String, password: String,
      database: String, sample: Profile) throws {
@@ -49,15 +49,15 @@ public class UDBMariaDB<Profile>: UserDatabase {
 
     guard db.setOption(.MYSQL_SET_CHARSET_NAME, "utf8mb4"),
       db.connect(host: host, user: user, password: password, db: database) else {
-        throw Exception.fault("connection failure")
+        throw Exception.connection
     }
     let properties = try DataworkUtility.explainProperties(of: sample)
     guard !properties.isEmpty else {
-      throw Exception.fault("invalid profile structure")
+      throw Exception.malformed
     }
     fields = try properties.map { s -> Field in
       guard let tp = DataworkUtility.ANSITypeOf(s.type) else {
-        throw Exception.fault("incompatible type name: \(s.type)")
+        throw Exception.unsupported
       }
       return Field(name: s.name, type: tp)
     }
@@ -69,7 +69,7 @@ public class UDBMariaDB<Profile>: UserDatabase {
     salt VARCHAR(256), shadow VARCHAR(1024), \(fieldDescription))
     """
     guard db.query(statement: sql) else {
-      throw Exception.fault("table creation failure")
+      throw Exception.operation
     }
     let sql2 = """
     CREATE TABLE IF NOT EXISTS tickets (
@@ -77,13 +77,13 @@ public class UDBMariaDB<Profile>: UserDatabase {
     expiration INTEGER)
     """
     guard db.query(statement: sql2) else {
-      throw Exception.fault("tickets table creation failure")
+      throw Exception.operation
     }
     let sql3 = """
     CREATE INDEX IF NOT EXISTS ticket_exp ON tickets( expiration)
     """
     guard db.query(statement: sql3) else {
-      throw Exception.fault("tickets index creation failure")
+      throw Exception.operation
     }
   }
 
@@ -93,7 +93,7 @@ public class UDBMariaDB<Profile>: UserDatabase {
 
   public func ban(_ ticket: String, _ expiration: time_t) throws {
     guard expiration > time(nil) else {
-      throw Exception.fault("ticket has already expired")
+      throw Exception.expired
     }
     self.autoflush()
 
@@ -102,12 +102,12 @@ public class UDBMariaDB<Profile>: UserDatabase {
     defer { stmt.close() }
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(ticket)
     stmt.bindParam(expiration)
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 
@@ -159,13 +159,13 @@ public class UDBMariaDB<Profile>: UserDatabase {
 
   public func insert<Profile>(_ record: UserRecord<Profile>) throws {
     if exists(record.id) {
-      throw Exception.fault("user has already registered")
+      throw Exception.violation
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       let dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     let properties:[String] = fields.map { $0.name }
     let columns = ["id", "salt", "shadow"] + properties
@@ -177,7 +177,7 @@ public class UDBMariaDB<Profile>: UserDatabase {
     defer { stmt.close() }
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(record.id)
     stmt.bindParam(record.salt)
@@ -187,19 +187,19 @@ public class UDBMariaDB<Profile>: UserDatabase {
       try stmt.bindParameter(x)
     }
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 
   public func update<Profile>(_ record: UserRecord<Profile>) throws {
     guard exists(record.id) else {
-      throw Exception.fault("user does not exists")
+      throw Exception.inexisting
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       let dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     let properties:[String] = fields.map { $0.name }
     let columns:[String] = fields.map { "\($0.name) = ?" }
@@ -208,7 +208,7 @@ public class UDBMariaDB<Profile>: UserDatabase {
     let stmt = MySQLStmt(db)
     defer { stmt.close() }
     guard stmt.prepare(statement: sql) else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
     stmt.bindParam(record.salt)
     stmt.bindParam(record.shadow)
@@ -218,7 +218,7 @@ public class UDBMariaDB<Profile>: UserDatabase {
     }
     stmt.bindParam(record.id)
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 
@@ -231,10 +231,10 @@ public class UDBMariaDB<Profile>: UserDatabase {
     defer { stmt.close() }
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(self.db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(id)
-    guard stmt.execute() else { throw Exception.fault(self.db.errorMessage())}
+    guard stmt.execute() else { throw Exception.operation }
     let fetched = stmt.results().forEachRow { rec in
       let _id = rec[0] as? String
       let _salt = rec[1] as? String
@@ -260,24 +260,24 @@ public class UDBMariaDB<Profile>: UserDatabase {
         debugPrint("json failure")
       }
     }
-    guard fetched, let v = u else { throw Exception.fault(self.db.errorMessage())}
+    guard fetched, let v = u else { throw Exception.operation }
     return v
   }
 
   public func delete(_ id: String) throws {
     guard exists(id) else {
-      throw Exception.fault("user does not exist")
+      throw Exception.inexisting
     }
     let stmt = MySQLStmt(db)
     defer { stmt.close() }
     let sql = "DELETE FROM users WHERE id = ?"
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(id)
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 }
diff --git a/Sources/UDBMySQL/UDBMySQL.swift b/Sources/UDBMySQL/UDBMySQL.swift
index 830c662..653f236 100644
--- a/Sources/UDBMySQL/UDBMySQL.swift
+++ b/Sources/UDBMySQL/UDBMySQL.swift
@@ -18,8 +18,8 @@ extension MySQLStmt {
     } else if x is [Int8], let y = x as? [Int8] {
       self.bindParam(y, length: y.count)
     } else {
-      let tp = type(of: x)
-      throw Exception.fault("incompatible type: \(tp)")
+      // let tp = type(of: x)
+      throw Exception.unsupported
     }
   }
 }
@@ -49,15 +49,15 @@ public class UDBMySQL<Profile>: UserDatabase {
 
     guard db.setOption(.MYSQL_SET_CHARSET_NAME, "utf8mb4"),
       db.connect(host: host, user: user, password: password, db: database) else {
-        throw Exception.fault("connection failure")
+        throw Exception.connection
     }
     let properties = try DataworkUtility.explainProperties(of: sample)
     guard !properties.isEmpty else {
-      throw Exception.fault("invalid profile structure")
+      throw Exception.malformed
     }
     fields = try properties.map { s -> Field in
       guard let tp = DataworkUtility.ANSITypeOf(s.type) else {
-        throw Exception.fault("incompatible type name: \(s.type)")
+        throw Exception.unsupported
       }
       return Field(name: s.name, type: tp)
     }
@@ -69,7 +69,7 @@ public class UDBMySQL<Profile>: UserDatabase {
     salt VARCHAR(256), shadow VARCHAR(1024), \(fieldDescription))
     """
     guard db.query(statement: sql) else {
-      throw Exception.fault("table creation failure")
+      throw Exception.operation
     }
     let sql2 = """
     CREATE TABLE IF NOT EXISTS tickets (
@@ -77,13 +77,13 @@ public class UDBMySQL<Profile>: UserDatabase {
     expiration INTEGER)
     """
     guard db.query(statement: sql2) else {
-      throw Exception.fault("tickets table creation failure")
+      throw Exception.operation
     }
     let sql3 = """
     CREATE INDEX IF NOT EXISTS ticket_exp ON tickets( expiration)
     """
     guard db.query(statement: sql3) else {
-      throw Exception.fault("tickets index creation failure")
+      throw Exception.operation
     }
   }
 
@@ -93,7 +93,7 @@ public class UDBMySQL<Profile>: UserDatabase {
 
   public func ban(_ ticket: String, _ expiration: time_t) throws {
     guard expiration > time(nil) else {
-      throw Exception.fault("ticket has already expired")
+      throw Exception.expired
     }
     self.autoflush()
 
@@ -102,12 +102,12 @@ public class UDBMySQL<Profile>: UserDatabase {
     defer { stmt.close() }
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(ticket)
     stmt.bindParam(expiration)
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 
@@ -159,13 +159,13 @@ public class UDBMySQL<Profile>: UserDatabase {
 
   public func insert<Profile>(_ record: UserRecord<Profile>) throws {
     if exists(record.id) {
-      throw Exception.fault("user has already registered")
+      throw Exception.violation
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       let dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     let properties:[String] = fields.map { $0.name }
     let columns = ["id", "salt", "shadow"] + properties
@@ -177,7 +177,7 @@ public class UDBMySQL<Profile>: UserDatabase {
     defer { stmt.close() }
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(record.id)
     stmt.bindParam(record.salt)
@@ -187,19 +187,19 @@ public class UDBMySQL<Profile>: UserDatabase {
       try stmt.bindParameter(x)
     }
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 
   public func update<Profile>(_ record: UserRecord<Profile>) throws {
     guard exists(record.id) else {
-      throw Exception.fault("user does not exists")
+      throw Exception.inexisting
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       let dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     let properties:[String] = fields.map { $0.name }
     let columns:[String] = fields.map { "\($0.name) = ?" }
@@ -208,7 +208,7 @@ public class UDBMySQL<Profile>: UserDatabase {
     let stmt = MySQLStmt(db)
     defer { stmt.close() }
     guard stmt.prepare(statement: sql) else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
     stmt.bindParam(record.salt)
     stmt.bindParam(record.shadow)
@@ -218,7 +218,7 @@ public class UDBMySQL<Profile>: UserDatabase {
     }
     stmt.bindParam(record.id)
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 
@@ -231,10 +231,10 @@ public class UDBMySQL<Profile>: UserDatabase {
     defer { stmt.close() }
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(self.db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(id)
-    guard stmt.execute() else { throw Exception.fault(self.db.errorMessage())}
+    guard stmt.execute() else { throw Exception.operation }
     let fetched = stmt.results().forEachRow { rec in
       let _id = rec[0] as? String
       let _salt = rec[1] as? String
@@ -260,24 +260,24 @@ public class UDBMySQL<Profile>: UserDatabase {
         debugPrint("json failure")
       }
     }
-    guard fetched, let v = u else { throw Exception.fault(self.db.errorMessage())}
+    guard fetched, let v = u else { throw Exception.operation }
     return v
   }
 
   public func delete(_ id: String) throws {
     guard exists(id) else {
-      throw Exception.fault("user does not exist")
+      throw Exception.inexisting
     }
     let stmt = MySQLStmt(db)
     defer { stmt.close() }
     let sql = "DELETE FROM users WHERE id = ?"
     guard stmt.prepare(statement: sql)
       else {
-        throw Exception.fault(db.errorMessage())
+        throw Exception.operation
     }
     stmt.bindParam(id)
     guard stmt.execute() else {
-      throw Exception.fault(db.errorMessage())
+      throw Exception.operation
     }
   }
 }
diff --git a/Sources/UDBPostgreSQL/UDBPostgreSQL.swift b/Sources/UDBPostgreSQL/UDBPostgreSQL.swift
index 189058e..097f133 100644
--- a/Sources/UDBPostgreSQL/UDBPostgreSQL.swift
+++ b/Sources/UDBPostgreSQL/UDBPostgreSQL.swift
@@ -25,18 +25,18 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
     db = PGConnection()
     let status = db.connectdb(connection)
     guard status == .ok else {
-      throw Exception.fault("Connection Failure, please check the connection string " + connection)
+      throw Exception.connection
     }
     touch = time(nil)
     encoder = JSONEncoder()
     decoder = JSONDecoder()
     let properties = try DataworkUtility.explainProperties(of: sample)
     guard !properties.isEmpty else {
-      throw Exception.fault("invalid profile structure")
+      throw Exception.malformed
     }
     fields = try properties.map { s -> Field in
       guard let tp = DataworkUtility.ANSITypeOf(s.type) else {
-        throw Exception.fault("incompatible type name: \(s.type)")
+        throw Exception.unsupported
       }
       return Field(name: s.name, type: tp)
     }
@@ -49,10 +49,10 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
     """
     let result = try db.execute(statement: sql)
     let s = result.status()
-    let r = result.errorMessage()
+    //let r = result.errorMessage()
     result.clear()
     guard s == .commandOK || s == .tuplesOK else {
-      throw Exception.fault(r)
+      throw Exception.operation
     }
     let sql2 = """
     CREATE TABLE IF NOT EXISTS tickets (
@@ -61,20 +61,20 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
     """
     let result2 = try db.execute(statement: sql2)
     let s2 = result2.status()
-    let r2 = result2.errorMessage()
+    //let r2 = result2.errorMessage()
     result2.clear()
     guard s2 == .commandOK || s2 == .tuplesOK else {
-      throw Exception.fault(r2)
+      throw Exception.operation
     }
     let sql3 = """
     CREATE INDEX IF NOT EXISTS ticket_exp ON tickets( expiration)
     """
     let result3 = try db.execute(statement: sql3)
     let s3 = result3.status()
-    let r3 = result3.errorMessage()
+    //let r3 = result3.errorMessage()
     result3.clear()
     guard s3 == .commandOK || s3 == .tuplesOK else {
-      throw Exception.fault(r3)
+      throw Exception.operation
     }
   }
 
@@ -84,17 +84,17 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
 
   public func ban(_ ticket: String, _ expiration: time_t) throws {
     guard expiration > time(nil) else {
-      throw Exception.fault("ticket has already expired")
+      throw Exception.expired
     }
     self.autoflush()
 
     let sql = "INSERT INTO tickets(id, expiration) VALUES ($1, $2)"
     let result = db.exec(statement: sql, params: [ticket, expiration])
     let s = result.status()
-    let r = result.errorMessage()
+    // let r = result.errorMessage()
     result.clear()
     guard s == .commandOK || s == .tuplesOK else {
-      throw Exception.fault(r)
+      throw Exception.operation
     }
   }
 
@@ -116,13 +116,13 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
 
   public func insert<Profile>(_ record: UserRecord<Profile>) throws {
     if exists(record.id) {
-      throw Exception.fault("user has already registered")
+      throw Exception.violation
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       var dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     dic["id"] = record.id
     dic["salt"] = record.salt
@@ -139,7 +139,7 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
       if let v = dic[columns[i]] {
         values.append(v)
       } else {
-        throw Exception.fault("unexpected field \(columns[i])")
+        throw Exception.unsupported
       }
     }
     let col = columns.joined(separator: ",")
@@ -147,22 +147,22 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
     sql = "INSERT INTO users (\(col)) VALUES(\(que))"
     let result = db.exec(statement: sql, params: values)
     let s = result.status()
-    let r = result.errorMessage()
+    // let r = result.errorMessage()
     result.clear()
     guard s == .commandOK || s == .tuplesOK else {
-      throw Exception.fault(r)
+      throw Exception.operation
     }
   }
 
   public func update<Profile>(_ record: UserRecord<Profile>) throws {
     guard exists(record.id) else {
-      throw Exception.fault("user does not exists")
+      throw Exception.inexisting
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       var dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     dic["salt"] = record.salt
     dic["shadow"] = record.shadow
@@ -177,7 +177,7 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
       if let v = dic[col] {
         values.append(v)
       } else {
-        throw Exception.fault("unexpected field: \(col)")
+        throw Exception.unsupported
       }
     }
     values.append(record.id)
@@ -186,24 +186,24 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
     let sql = "UPDATE users SET \(sentence) WHERE id = $\(idNum)"
     let result = db.exec(statement: sql, params: values)
     let s = result.status()
-    let r = result.errorMessage()
+    // let r = result.errorMessage()
     result.clear()
     guard s == .commandOK || s == .tuplesOK else {
-      throw Exception.fault(r)
+      throw Exception.operation
     }
   }
 
   public func delete(_ id: String) throws {
     guard exists(id) else {
-      throw Exception.fault("user does not exist")
+      throw Exception.violation
     }
     let sql = "DELETE FROM users WHERE id = $1"
     let result = db.exec(statement: sql, params: [id])
     let s = result.status()
-    let r = result.errorMessage()
+    // let r = result.errorMessage()
     result.clear()
     guard s == .commandOK || s == .tuplesOK else {
-      throw Exception.fault(r)
+      throw Exception.operation
     }
   }
 
@@ -213,18 +213,18 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
     let  sql = "SELECT id, salt, shadow, \(col) FROM users WHERE id = $1 LIMIT 1"
     let r = db.exec(statement: sql, params: [id])
     let s = r.status()
-    let msg = r.errorMessage()
+    // let msg = r.errorMessage()
     guard s == .commandOK || s == .tuplesOK,
       r.numTuples() == 1 else {
         r.clear()
-        throw Exception.fault(msg)
+        throw Exception.operation
     }
     guard let uid = r.getFieldString(tupleIndex: 0, fieldIndex: 0),
       let salt = r.getFieldString(tupleIndex: 0, fieldIndex: 1),
       let shadown = r.getFieldString(tupleIndex: 0, fieldIndex: 2),
       uid == id else {
         r.clear()
-        throw Exception.fault("unexpected select result")
+        throw Exception.operation
     }
     var dic: [String: Any] = [:]
     for i in 0 ..< fields.count {
@@ -248,7 +248,7 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
       } else if tp == "BLOB" {
         dic[fields[i].name] = r.getFieldBlob(tupleIndex: 0, fieldIndex: j)
       } else {
-        throw Exception.fault("incompatible SQL type \(tp)")
+        throw Exception.unsupported
       }
     }
     r.clear()
@@ -259,7 +259,7 @@ public class UDBPostgreSQL<Profile>: UserDatabase {
       let u = UserRecord(id: id, salt: salt, shadow: shadown, profile: profile)
       return u
     } catch {
-      throw Exception.fault("json encoding / decoding failure")
+      throw Exception.json
     }
   }
 
diff --git a/Sources/UDBSQLite/UDBSQLite.swift b/Sources/UDBSQLite/UDBSQLite.swift
index d95f598..b2d943e 100644
--- a/Sources/UDBSQLite/UDBSQLite.swift
+++ b/Sources/UDBSQLite/UDBSQLite.swift
@@ -34,7 +34,7 @@ public class UDBSQLite<Profile>: UserDatabase {
 
     let properties = try DataworkUtility.explainProperties(of: sample)
     guard !properties.isEmpty else {
-      throw Exception.fault("invalid profile structure")
+      throw Exception.malformed
     }
     fields = try properties.map { s -> Field in
       let tp = s.type
@@ -48,7 +48,7 @@ public class UDBSQLite<Profile>: UserDatabase {
       } else if tp == "String" {
         typeName = "TEXT"
       } else {
-        throw Exception.fault("incompatible type name: \(tp)")
+        throw Exception.unsupported
       }
       return Field(name: s.name, type: typeName)
     }
@@ -76,7 +76,7 @@ public class UDBSQLite<Profile>: UserDatabase {
 
   public func ban(_ ticket: String, _ expiration: time_t) throws {
     guard expiration > time(nil) else {
-      throw Exception.fault("ticket has already expired")
+      throw Exception.expired
     }
     self.autoflush()
 
@@ -122,13 +122,13 @@ public class UDBSQLite<Profile>: UserDatabase {
 
   public func insert<Profile>(_ record: UserRecord<Profile>) throws {
     if exists(record.id) {
-      throw Exception.fault("user has already registered")
+      throw Exception.violation
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       let dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     let properties:[String] = fields.map { $0.name }
     let columns = ["id", "salt", "shadow"] + properties
@@ -158,7 +158,7 @@ public class UDBSQLite<Profile>: UserDatabase {
           try stmt.bind(position: j, s)
           break
         default:
-          throw Exception.fault("incompatible value type")
+          throw Exception.unsupported
         }
       }
     }
@@ -188,7 +188,7 @@ public class UDBSQLite<Profile>: UserDatabase {
         case "REAL":
           dic[fname] = rec.columnDouble(position: j)
         default:
-          throw Exception.fault("unexpected column type: \(fields[i].type)")
+          throw Exception.unsupported
         }
       }
       let json = try dic.jsonEncodedString()
@@ -197,14 +197,14 @@ public class UDBSQLite<Profile>: UserDatabase {
       u = UserRecord(id: id, salt: salt, shadow: shadow, profile: profile)
     }
     guard let v = u else {
-      throw Exception.fault("record not found")
+      throw Exception.inexisting
     }
     return v
   }
 
   public func delete(_ id: String) throws {
     guard exists(id) else {
-      throw Exception.fault("user does not exists")
+      throw Exception.inexisting
     }
     let sql = "DELETE FROM users WHERE id = ?"
     try db.execute(statement: sql){
@@ -215,13 +215,13 @@ public class UDBSQLite<Profile>: UserDatabase {
 
   public func update<Profile>(_ record: UserRecord<Profile>) throws {
     guard exists(record.id) else {
-      throw Exception.fault("user does not exists")
+      throw Exception.inexisting
     }
     let data = try encoder.encode(record.profile)
     let bytes:[UInt8] = data.map { $0 }
     guard let json = String(validatingUTF8:bytes),
       let dic = try json.jsonDecode() as? [String: Any] else {
-        throw Exception.fault("json encoding failure")
+        throw Exception.json
     }
     let columns:[String] = fields.map { "\($0.name) = ?" }
     let sentence = columns.joined(separator: ",")
@@ -250,7 +250,7 @@ public class UDBSQLite<Profile>: UserDatabase {
           let s = dic[f.name] as? [Int8] ?? []
           try stmt.bind(position:j, s)
         default:
-          throw Exception.fault("incompatible value type")
+          throw Exception.unsupported
         }
       }
       try stmt.bind(position: fields.count + 3, record.id)
diff --git a/Tests/PerfectSSOAuthTests/PerfectSSOAuthTests.swift b/Tests/PerfectSSOAuthTests/PerfectSSOAuthTests.swift
index cca8a9f..55cd2b3 100644
--- a/Tests/PerfectSSOAuthTests/PerfectSSOAuthTests.swift
+++ b/Tests/PerfectSSOAuthTests/PerfectSSOAuthTests.swift
@@ -24,13 +24,13 @@ class PerfectSSOAuthTests: XCTestCase {
   let godpass = "rockford"
   let badpass = "treefrog"
   let folder = "/tmp"
-  let sqlite = "/tmp/users.db"
+  let sqlite = "/tmp/user.db"
   let mysql_hst = "maria"
   let mysql_usr = "root"
   let mysql_pwd = "rockford"
   let mysql_dbt = "test"
   let pgsql_usr = "rocky"
-  let table = "users"
+
   let profile = Profile(firstName: "rocky", lastName: "wei", age: 21, email: "rocky@perfect.org")
   let log = FileLogger("/tmp", GMT: false)
   let pgconnection = "postgresql://rocky:rockford@maria/test"
@@ -108,15 +108,15 @@ class PerfectSSOAuthTests: XCTestCase {
       let rocky = try manager.load(id: username)
       print(rocky)
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
     do {
       let manager = LoginManager<Profile>(udb: udb, log: log)
       _ = try manager.login(id: username, password: badpass)
-    } catch Exception.fault(let reason) {
-      print("expected error:", reason)
+    } catch Exception.access {
+      print("expected access denied")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
     do {
       let manager = LoginManager<Profile>(udb: udb, log: log)
@@ -130,14 +130,14 @@ class PerfectSSOAuthTests: XCTestCase {
       let y = try manager.verify(token: tok2)
       XCTAssertEqual(x.content["iss"] as? String ?? "X", y.content["iss"] as? String ?? "Y")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
     do {
       let manager = LoginManager<Profile>(udb: udb, log: log)
       try manager.update(id: username, password: badpass)
       _ = try manager.login(id: username, password: badpass)
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
     do {
       let manager = LoginManager<Profile>(udb: udb, log: log, recycle: 3)
@@ -157,7 +157,7 @@ class PerfectSSOAuthTests: XCTestCase {
       let y2 = try? manager.verify(token: token2)
       XCTAssertNil(y2)
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
     do {
       let manager = LoginManager<Profile>(udb: udb, log: log)
@@ -177,13 +177,13 @@ class PerfectSSOAuthTests: XCTestCase {
   func testPostgreSQL() {
     let pg = PGConnection()
     _ = pg.connectdb(pgconnection)
-    _ = pg.exec(statement: "DROP TABLE \(table)")
+    _ = pg.exec(statement: "DROP TABLE users")
     _ = pg.exec(statement: "DROP TABLE tickets")
     do {
       let udb = try UDBPostgreSQL<Profile>(connection: pgconnection, sample: profile)
       testStandard(udb: udb, label: "postgresql")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
   }
   func testMariaDB() {
@@ -192,14 +192,14 @@ class PerfectSSOAuthTests: XCTestCase {
       XCTFail("connection failure")
       return
     }
-    _ = mysql.query(statement: "DROP TABLE \(table)")
+    _ = mysql.query(statement: "DROP TABLE users")
     _ = mysql.query(statement: "DROP TABLE tickets")
     do {
       let udb = try UDBMariaDB<Profile>(host: mysql_hst, user: mysql_usr,
        password: mysql_pwd, database: mysql_dbt, sample: profile)
       testStandard(udb: udb, label: "mariadb")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
   }
   func testMySQL() {
@@ -208,14 +208,14 @@ class PerfectSSOAuthTests: XCTestCase {
       XCTFail("connection failure")
       return
     }
-    _ = mysql.query(statement: "DROP TABLE \(table)")
+    _ = mysql.query(statement: "DROP TABLE users")
     _ = mysql.query(statement: "DROP TABLE tickets")
     do {
       let udb = try UDBMySQL<Profile>(host: mysql_hst, user: mysql_usr,
       password: mysql_pwd, database: mysql_dbt, sample: profile)
       testStandard(udb: udb, label: "mysql")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
   }
   func testSQLite() {
@@ -224,7 +224,7 @@ class PerfectSSOAuthTests: XCTestCase {
       let udb = try UDBSQLite<Profile>(path: sqlite, sample: profile)
       testStandard(udb: udb, label: "sqlite")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
   }
   func testJSONDir() {
@@ -233,7 +233,7 @@ class PerfectSSOAuthTests: XCTestCase {
       let udb = try UDBJSONFile<Profile>(directory: folder)
       testStandard(udb: udb, label: "jsonfile")
     } catch {
-      XCTFail(error.localizedDescription)
+      XCTFail("\(error)")
     }
   }
 }