feat(020): readme, upgrade test env (#5)

.env

@@ -1 +1 @@
-OPENMLDB_VERSION=0.8.4
+OPENMLDB_VERSION=0.8.5

README.md

@@ -0,0 +1,79 @@
+OpenMLDB Go SDK
+------
+
+Pure Go [OpenMLDB](https://github.com/4paradigm/OpenMLDB) driver for database/sql, connect via HTTP.
+
+## Features
+
+## Requirements
+
+- OpenMLDB with all components version >= 0.6.2
+- OpenMLDB API Server setted up
+
+## Installation
+
+```sh
+go get github.com/4paradigm/openmldb-go-sdk
+```
+
+## Data Source Name (DSN)
+
+```
+openmldb://<API_SERVER_HOST>:<API_SERVER_PORT>/<DB_NAME>
+```
+
+For example, to open a database to `test_db` by api server at `127.0.0.1:8080`:
+```go
+db, err := sql.Open("openmldb", "openmldb://127.0.0.1:8080/test_db")
+```
+
+## Getting Start
+
+```go
+package main
+
+import (
+  "context"
+  "database/sql"
+
+  _ "github.com/4paradigm/openmldb-go-sdk"
+)
+
+func main() {
+  db, err := sql.Open("openmldb", "openmldb://127.0.0.1:8080/test_db")
+  if err != nil {
+    panic(err)
+  }
+
+  defer db.Close()
+
+  ctx := context.Background()
+
+  // execute DDL
+  if _, err := db.ExecContext(ctx, `CREATE TABLE demo (c1 int, c2 string);`); err != nil {
+    panic(err)
+  }
+
+  // execute DML
+  if _, err := db.ExecContext(ctx, `INSERT INTO demo VALUES (1, "bb"), (2, "bb");`); err != nil {
+    panic(err)
+  }
+
+  // execute DQL
+  rows, err := db.QueryContext(ctx, `SELECT c1, c2 FROM demo;`)
+  if err != nil{
+    panic(err)
+  }
+
+  var col1 int
+  var col2 string
+
+  // iterating query result
+  for rows.Next() {
+    if err := rows.Scan(&col1, &col2); err != nil {
+      panic(err)
+    }
+    println(col1, col2)
+  }
+}
+```