Suppose I have this table:
id | name | city
------------------
1 | n1 | c1
2 | n2 | c2
3 | n3 | c3
4 | n4 | c4
I want to check if the value c7
exists under the variable city
or not.
If it does, I will do something.
If it doesn't, I will do something else.
SELECT
IF city='C7'
THEN city
ELSE 'somethingelse'
END as `city`
FROM `table` WHERE `city` = 'c7'
For Matching the ID:
Select * from table_name where 1=1
For Matching the Pattern:
Select * from table_name column_name Like '%string%'
This works for me :
$db = mysqli_connect('localhost', 'UserName', 'Password', 'DB_Name') or die('Not Connected');
mysqli_set_charset($db, 'utf8');
$sql = mysqli_query($db,"SELECT * FROM `mytable` WHERE city='c7'");
$sql = mysqli_fetch_assoc($sql);
$Checker = $sql['city'];
if ($Checker != null) {
echo 'Already exists';
} else {
echo 'Not found';
}
Assuming the connection is established and is available in global scope;
//Check if a value exists in a table
function record_exists ($table, $column, $value) {
global $connection;
$query = "SELECT * FROM {$table} WHERE {$column} = {$value}";
$result = mysql_query ( $query, $connection );
if ( mysql_num_rows ( $result ) ) {
return TRUE;
} else {
return FALSE;
}
}
Usage: Assuming that the value to be checked is stored in the variable $username;
if (record_exists ( 'employee', 'username', $username )){
echo "Username is not available. Try something else.";
} else {
echo "Username is available";
}
"SELECT * FROM yourTable WHERE city = 'c7'"
"SELECT * FROM yourTable WHERE city LIKE '%c7%'"
Of course you can change '%c7%'
to '%c7'
or 'c7%'
depending on how you want to search it. For exact match, use first query example.
$result = mysql_query("SELECT * FROM yourTable WHERE city = 'c7'");
$matchFound = mysql_num_rows($result) > 0 ? 'yes' : 'no';
echo $matchFound;
You can also use if
condition there.
I tried to d this for a while and
$sqlcommand = 'SELECT * FROM database WHERE search="'.$searchString.'";';
just works if there are TWO identical entries, but,
if you replace
$sth = $db->prepare($sqlcommand);
$sth->execute();
$record = $sth->fetch();
if ($sth->fetchColumn() > 0){}if ($sth->fetchColumn() > 0){}
with
if ($result){}
it works with only one matching record, hope this helps.
Source: Stackoverflow.com