Odbc Demo

OdbcDemo.go

////////////////////////////////////////////////////////////////////////////
// Porgram: OdbcDemo
// Purpose: Go MSSQL odbc demo, using the code.google.com/p/odbc driver
// Authors: Tong Sun (c) 2013, All rights reserved
////////////////////////////////////////////////////////////////////////////

// Style: gofmt -tabs=false -tabwidth=2 -w

package main

import (
	"database/sql"
	"fmt"
	"log"

	_ "github.com/alexbrainman/odbc"
)

/*
Notice: Load the driver anonymously, aliasing its package qualifier to _
so none of its exported names are visible to our code. Under the hood,
the driver registers itself as being available to the database/sql package,
but in general nothing else happens.
-- https://github.com/VividCortex/go-database-sql-tutorial
*/

func main() {
	conn, err := sql.Open("odbc",
		"driver=sql server;server=localhost;database=tempdb;trusted_connection=yes;")
	if err != nil {
		fmt.Println("Connecting Error")
		return
	}
	defer conn.Close()
	fmt.Println("Sql Server Connected")

	stmt, err := conn.Prepare("select top 5 database_id, name from sys.databases WHERE database_id >= 5")
	if err != nil {
		fmt.Println("Query Preparation Error", err)
		return
	}
	defer stmt.Close()
	fmt.Println("Query Prepared")

	// Use db.Query() to send the query to the database. Check errors as usual.
	row, err := stmt.Query()
	if err != nil {
		fmt.Println("Query Error", err)
		return
	}
	defer row.Close()

	// Iterate over the row with row.Next()
	// and read the columns in each row into variables with row.Scan()
	fmt.Printf("\nResult set 1:\n")
	for row.Next() {
		//var id int
		var (
			id   int
			name string
		)
		if err := row.Scan(&id, &name); err == nil {
			fmt.Println(id, name)
		}
	}
	// Check for errors after done iterating over the row. Should always do.
	err = row.Err()
	if err != nil {
		fmt.Printf("\nFatal: %s\n", err)
	}

	// Preparing Queries
	/*
		You should, in general, always prepare queries to be used multiple times.
		The result of preparing the query is a prepared statement, which can
		have ? placeholders for parameters that you'll provide when you execute
		the statement. This is much better than concatenating strings.
	*/

	stmt, err = conn.Prepare("select top 5 database_id, name from sys.databases WHERE database_id >= ?")
	if err != nil {
		log.Fatal(err)
	}

	row, err = stmt.Query(1)
	if err != nil {
		log.Fatal(err)
	}
	defer row.Close()

	fmt.Printf("\nResult set 2:\n")
	for row.Next() {
		var (
			id   int
			name string
		)
		if err := row.Scan(&id, &name); err == nil {
			fmt.Println(id, name)
		} else {
			log.Fatal(err)
		}
	}
	err = row.Err()
	if err != nil {
		log.Fatal(err)
	}

	fmt.Printf("\nFinished correctly\n")
	return
}