[KYUUBI #5969] Trino engine add default schema

# 🔍 Description
## Issue References 🔗

This pull request fixes #5969

## Describe Your Solution 🔧

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

## Types of changes 🔖

- [x] Bugfix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)

## Test Plan 🧪

#### Behavior Without This Pull Request ⚰️

#### Behavior With This Pull Request 🎉

#### Related Unit Tests

---

# Checklist 📝

- [x] This patch was not authored or co-authored using [Generative Tooling](https://www.apache.org/legal/generative-tooling.html)

**Be nice. Be informative.**

Closes #5971 from lsm1/branch-kyuubi-trino-schema.

Closes #5969

dfc987e [senmiaoliu] trino engine add default result schema

Authored-by: senmiaoliu <[email protected]>
Signed-off-by: Cheng Pan <[email protected]>
(cherry picked from commit fcad8b5)
Signed-off-by: Cheng Pan <[email protected]>

externals/kyuubi-trino-engine/src/main/scala/org/apache/kyuubi/engine/trino/TrinoStatement.scala

@@ -25,6 +25,7 @@ import scala.concurrent.ExecutionContext
 
 import com.google.common.base.Verify
 import io.trino.client.ClientSession
+import io.trino.client.ClientTypeSignature
 import io.trino.client.Column
 import io.trino.client.StatementClient
 import io.trino.client.StatementClientFactory
@@ -46,6 +47,9 @@ class TrinoStatement(
     sql: String,
     operationLog: Option[OperationLog]) extends Logging {
 
+  private val defaultSchema: List[Column] =
+    List(new Column("Result", "VARCHAR", new ClientTypeSignature("VARCHAR")))
+
   private lazy val trino = StatementClientFactory
     .newStatementClient(trinoContext.httpClient, trinoContext.clientSession.get, sql)
 
@@ -68,6 +72,9 @@ class TrinoStatement(
       val columns = results.getColumns()
       if (columns != null) {
         info(s"Execute with Trino query id: ${results.getId}")
+        if (columns.isEmpty) {
+          return defaultSchema
+        }
         return columns.asScala.toList
       }
       trino.advance()