feat: add execute_update example for go

Author: niebayes

go/client.go

@@ -102,6 +102,16 @@ func (client *Client) Execute(sql string) ([]arrow.Record, error) {
 	return client.doGet(flightInfo.GetEndpoint()[0].GetTicket())
 }
 
+// Executes the sql on Datalayers and returns the affected rows.
+// The supported sqls are Insert and Delete. Note, the development for supporting Delete is in progress.
+func (client *Client) ExecuteUpdate(sql string) (int64, error) {
+	affectedRows, err := client.inner.ExecuteUpdate(client.ctx, sql)
+	if err != nil {
+		return 0, fmt.Errorf("failed to execute a sql: %v", err)
+	}
+	return affectedRows, nil
+}
+
 // Creates a prepared statement.
 func (client *Client) Prepare(sql string) (*flightsql.PreparedStatement, error) {
 	return client.inner.Prepare(client.ctx, sql)
@@ -119,6 +129,11 @@ func (client *Client) ExecutePrepared(preparedStmt *flightsql.PreparedStatement,
 	return client.doGet(flightInfo.GetEndpoint()[0].GetTicket())
 }
 
+// Closes the prepared statement.
+func (client *Client) ClosePrepared(preparedStmt *flightsql.PreparedStatement) error {
+	return preparedStmt.Close(client.ctx)
+}
+
 // Calls the `DoGet` method of the FlightSQL client.
 func (client *Client) doGet(ticket *flight.Ticket) ([]arrow.Record, error) {
 	reader, err := client.inner.DoGet(client.ctx, ticket)

go/main.go

@@ -147,4 +147,40 @@ func main() {
 	//    2024-09-01 10:05:00 +0800 CST     2   15.30      1
 	//    2024-09-02 10:05:00 +0800 CST     2   15.30      1
 	PrintRecords(result)
+
+	// Closes the prepared statement to notify releasing resources on server side.
+	if err = client.ClosePrepared(preparedStmt); err != nil {
+		fmt.Println("Failed to close a prepared statement: ", err)
+		return
+	}
+
+	// There provides a dedicated interface `execute_update` for executing DMLs, including Insert, Delete.
+	// This interface directly returns the affected rows which might be convenient for some use cases.
+	//
+	// Note, Datalayers does not support Update and the development for Delete is in progress.
+	sql = `
+        INSERT INTO go.demo (ts, sid, value, flag) VALUES
+            ('2024-09-03T10:00:00+08:00', 1, 4.5, 0),
+            ('2024-09-03T10:05:00+08:00', 2, 11.6, 1);`
+	affectedRows, err := client.ExecuteUpdate(sql)
+	if err != nil {
+		fmt.Println("Failed to insert data: ", err)
+		return
+	}
+	// The output should be:
+	// Affected rows: 2
+	fmt.Println("Affected rows: ", affectedRows)
+
+	// Checks that the data are inserted successfully.
+	sql = "SELECT * FROM go.demo where ts >= '2024-09-03T10:00:00+08:00'"
+	result, err = client.Execute(sql)
+	if err != nil {
+		fmt.Println("Failed to scan data: ", err)
+		return
+	}
+	// The result should be:
+	// 	                              ts   sid   value   flag
+	//    2024-09-03 10:00:00 +0800 CST     1    4.50      0
+	//    2024-09-03 10:05:00 +0800 CST     2   11.60      1
+	PrintRecords(result)
 }