Update SQL Server driver library

vendor/github.com/denisenkom/go-mssqldb/newconnector_example_test.go

@@ -0,0 +1,143 @@
+// +build go1.10
+
+package mssql_test
+
+import (
+	"context"
+	"database/sql"
+	"flag"
+	"fmt"
+	"log"
+	"net/url"
+	"strconv"
+
+	mssql "github.com/denisenkom/go-mssqldb"
+)
+
+var (
+	debug         = flag.Bool("debug", false, "enable debugging")
+	password      = flag.String("password", "", "the database password")
+	port     *int = flag.Int("port", 1433, "the database port")
+	server        = flag.String("server", "", "the database server")
+	user          = flag.String("user", "", "the database user")
+)
+
+const (
+	createTableSql      = "CREATE TABLE TestAnsiNull (bitcol bit, charcol char(1));"
+	dropTableSql        = "IF OBJECT_ID('TestAnsiNull', 'U') IS NOT NULL DROP TABLE TestAnsiNull;"
+	insertQuery1        = "INSERT INTO TestAnsiNull VALUES (0, NULL);"
+	insertQuery2        = "INSERT INTO TestAnsiNull VALUES (1, 'a');"
+	selectNullFilter    = "SELECT bitcol FROM TestAnsiNull WHERE charcol = NULL;"
+	selectNotNullFilter = "SELECT bitcol FROM TestAnsiNull WHERE charcol <> NULL;"
+)
+
+func makeConnURL() *url.URL {
+	return &url.URL{
+		Scheme: "sqlserver",
+		Host:   *server + ":" + strconv.Itoa(*port),
+		User:   url.UserPassword(*user, *password),
+	}
+}
+
+// This example shows the usage of Connector type
+func ExampleConnector() {
+	flag.Parse()
+
+	if *debug {
+		fmt.Printf(" password:%s\n", *password)
+		fmt.Printf(" port:%d\n", *port)
+		fmt.Printf(" server:%s\n", *server)
+		fmt.Printf(" user:%s\n", *user)
+	}
+
+	connString := makeConnURL().String()
+	if *debug {
+		fmt.Printf(" connString:%s\n", connString)
+	}
+
+	// Create a new connector object by calling NewConnector
+	connector, err := mssql.NewConnector(connString)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+
+	// Use SessionInitSql to set any options that cannot be set with the dsn string
+	// With ANSI_NULLS set to ON, compare NULL data with = NULL or <> NULL will return 0 rows
+	connector.SessionInitSQL = "SET ANSI_NULLS ON"
+
+	// Pass connector to sql.OpenDB to get a sql.DB object
+	db := sql.OpenDB(connector)
+	defer db.Close()
+
+	// Create and populate table
+	_, err = db.Exec(createTableSql)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	defer db.Exec(dropTableSql)
+	_, err = db.Exec(insertQuery1)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	_, err = db.Exec(insertQuery2)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+
+	var bitval bool
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// (*Row) Scan should return ErrNoRows since ANSI_NULLS is set to ON
+	err = db.QueryRowContext(ctx, selectNullFilter).Scan(&bitval)
+	if err != nil {
+		if err.Error() != "sql: no rows in result set" {
+			log.Println(err)
+			return
+		}
+	} else {
+		log.Println("Expects an ErrNoRows error. No error is returned")
+		return
+	}
+
+	// (*Row) Scan should return ErrNoRows since ANSI_NULLS is set to ON
+	err = db.QueryRowContext(ctx, selectNotNullFilter).Scan(&bitval)
+	if err != nil {
+		if err.Error() != "sql: no rows in result set" {
+			log.Println(err)
+			return
+		}
+	} else {
+		log.Println("Expects an ErrNoRows error. No error is returned")
+		return
+	}
+
+	// Set ANSI_NULLS to OFF
+	connector.SessionInitSQL = "SET ANSI_NULLS OFF"
+
+	// (*Row) Scan should copy data to bitval
+	err = db.QueryRowContext(ctx, selectNullFilter).Scan(&bitval)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	if bitval != false {
+		log.Println("Incorrect value retrieved.")
+		return
+	}
+
+	// (*Row) Scan should copy data to bitval
+	err = db.QueryRowContext(ctx, selectNotNullFilter).Scan(&bitval)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	if bitval != true {
+		log.Println("Incorrect value retrieved.")
+		return
+	}
+}