MS SQL Server Interview Question:

PHP ODBC - How To Include Text Values in SQL Statements?

Submitted by: Administrator

Text values in SQL statements should be quoted with single quotes ('). If the text value contains a single quote ('), it should be protected by replacing it with two single quotes (''). In SQL language syntax, two single quotes represents one single quote in string literals.

The tutorial exercise below shows you two INSERT statements. The first one will fail, because it has an un-protected single quote. The second one will be ok, because a str_replace() is used to replace (') with (''):

<?php
$con = odbc_connect('ggl_SQL_SERVER','sa','GGL');
$notes = "It's a search engine!";
$sql = "INSERT INTO ggl_links (id, url, notes) VALUES ("
. " 201, 'www.google.com', '".$notes."')";
if (!odbc_exec($con, $sql)) {
print("SQL statement failed with error: ");
print(odbc_error($con).": ".odbc_errormsg($con)." ");
} else {
print("1 rows inserted. ");
}

$notes = "It's another search engine!";
$notes = str_replace("'", "''", $notes);
$sql = "INSERT INTO ggl_links (id, url, notes) VALUES ("
. " 202, 'www.yahoo.com', '".$notes."')";

Submitted by: Administrator

if (!odbc_exec($con, $sql)) {
print("SQL statement failed with error: ");
print(odbc_error($con).": ".odbc_errormsg($con)." ");
} else {
print("1 rows inserted. ");
}

odbc_close($con);
?>

If you run this script, you will get something like this:

SQL statement failed with error:
37000: [Microsoft][ODBC SQL Server Driver][SQL Server]
Incorrect syntax near 's'.

1 rows inserted.

Submitted by: Administrator