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PHP MSSQL - How To Create an Identity Column?

Answers:

Answer #1
Many tables require an ID column to assign a unique ID number for each row in the table. For example, if you have a table to hold forum member profiles, you need an ID number to identify each member. To allow SQL Server to automatically assign a new ID number for each new record, you can define the ID column with IDENTITY attribute as shown in the following sample script:

<?php
$con = mssql_connect('LOCALHOST','sa','GlobalGuideLine');
mssql_select_db('GlobalGuideLineDatabase', $con);

$sql = "CREATE TABLE ggl_users ("
. " id INTEGER IDENTITY NOT NULL"
. ", name VARCHAR(80) NOT NULL"
. ", email VARCHAR(80) NULL"
. ", time DATETIME NULL"
. ")";
$res = mssql_query($sql, $con);
if (!$res) {
print("Table creation failed with error: ");
print(" ".mssql_get_last_message()." ");
} else {
print("Table ggl_users created. ");
}

mssql_close($con);
?>


Answer #2
If you run this script, a new table will be created with ID column defined as an identity column. It value will be auto-assigned each time a new record is inserted with an auto-incremented number. The sample script below inserts two records with ID values assigned by SQL Server:

<?php
$con = mssql_connect('LOCALHOST','sa','GlobalGuideLine');
mssql_select_db('GlobalGuideLineDatabase', $con);

$sql = "INSERT INTO ggl_users (name)"
. " VALUES ('John King')";
$res = mssql_query($sql, $con);

$sql = "INSERT INTO ggl_users (name)"
. " VALUES ('Nancy Greenberg')";
$res = mssql_query($sql, $con);

$sql = "SELECT id, name, time FROM ggl_users";
$res = mssql_query($sql, $con);
while ($row = mssql_fetch_array($res)) {
print($row['id'].", ".$row['name'].", "
. $row['time']." ");
}
mssql_free_result($res);

mssql_close($con);
?>

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

1, John King,
2, Nancy Greenberg,


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