feat: add more example for querying with prepare statement

Author: logo306142054

go/client.go

@@ -168,7 +168,7 @@ func (client *Client) ClosePrepared(preparedStmt *flightsql.PreparedStatement) e
 func (client *Client) doGet(ticket *flight.Ticket) ([]arrow.Record, error) {
 	ctx, cancel := client.timeoutContext()
 	reader, err := client.inner.DoGet(ctx, ticket)
-	cancel()
+	defer cancel()
 	if err != nil {
 		return nil, fmt.Errorf("failed to perform DoGet: %v", err)
 	}

go/main.go

@@ -28,7 +28,7 @@ func main() {
 	}
 
 	// Creates a database `go`.
-	sql := "CREATE DATABASE go;"
+	sql := "CREATE DATABASE if not exists go;"
 	result, err := client.Execute(sql)
 	if err != nil {
 		fmt.Println("Failed to create database: ", err)
@@ -46,7 +46,7 @@ func main() {
 
 	// Creates a table `demo` within the database `go`.
 	sql = `
-    CREATE TABLE go.demo (
+    CREATE TABLE if not exists go.demo (
         ts TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
         sid INT32,
         value REAL,
@@ -148,6 +148,21 @@ func main() {
 	//    2024-09-02 10:05:00 +0800 CST     2   15.30      1
 	PrintRecords(result)
 
+	sql = "SELECT * FROM go.demo WHERE sid in (?, ?, ?)"
+	preparedStmt, err = dbClient.Prepare(sql)
+	if err != nil {
+		fmt.Println("Failed to create a select prepared statement: ", err)
+		return
+	}
+	// Retrieves all rows where `sid` in (1, 2, 3).
+	binding = MakeMultiBinding([]int32{1, 2, 3})
+	result, err = dbClient.ExecutePrepared(preparedStmt, binding)
+	if err != nil {
+		fmt.Println("Failed to execute a select prepared statement: ", err)
+		return
+	}
+	PrintRecords(result)
+
 	// Closes the prepared statement to notify releasing resources on server side.
 	if err = dbClient.ClosePrepared(preparedStmt); err != nil {
 		fmt.Println("Failed to close a prepared statement: ", err)

go/util.go

@@ -132,6 +132,31 @@ func MakeQueryBinding(sid int32) arrow.Record {
 	return record
 }
 
+func MakeMultiBinding(sids []int32) arrow.Record {
+	sidBuilder := array.NewInt32Builder(memory.NewGoAllocator())
+	defer sidBuilder.Release()
+	sidBuilder.Append(1)
+	sidArray1 := sidBuilder.NewArray()
+
+	sidBuilder = array.NewInt32Builder(memory.NewGoAllocator())
+	defer sidBuilder.Release()
+	sidBuilder.Append(2)
+	sidArray2 := sidBuilder.NewArray()
+
+	sidBuilder = array.NewInt32Builder(memory.NewGoAllocator())
+	defer sidBuilder.Release()
+	sidBuilder.Append(3)
+	sidArray3 := sidBuilder.NewArray()
+
+	schema := arrow.NewSchema([]arrow.Field{
+		{Name: "sid", Type: arrow.PrimitiveTypes.Int32, Nullable: true},
+		{Name: "sid", Type: arrow.PrimitiveTypes.Int32, Nullable: true},
+		{Name: "sid", Type: arrow.PrimitiveTypes.Int32, Nullable: true},
+	}, nil)
+	record := array.NewRecord(schema, []arrow.Array{sidArray1, sidArray2, sidArray3}, 1)
+	return record
+}
+
 func releaseRecords(records []arrow.Record) {
 	for _, record := range records {
 		record.Release()