MySQL Search tables by column name

SELECT DISTINCT TABLE_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME IN ('column_X','column_Y');

INSERT to a table by SELECT

INSERT INTO Target_Table (col1, col2, col3)
SELECT col1,col2,col3
FROM Source_Table

http://dev.mysql.com/doc/refman/5.5/en/insert.html

Get values from 2 queries

select (a.count1/b.count2) as result from
(SELECT count(*) as count1 FROM table1) as a,
(SELECT count(*) as count2 FROM table2) as b

Date comparison

if(strtotime("now") < strtotime('2012-08-21 9:54')){
    echo  "something... ";
}

Get value of HTML select box

function get_selected_value(name){
   var sele = document.getElementById( name );
   var selected_value = sele.options[sele.selectedIndex].value;
   return selected_value;
}

Escapes special characters in a string for SQL

PHP function:

mysql_real_escape_string()




  //This stops SQL Injection in POST vars
  foreach ($_POST as $key => $value) {
    $_POST[$key] = mysql_real_escape_string($value);
  }

  //This stops SQL Injection in GET vars
  foreach ($_GET as $key => $value) {
    $_GET[$key] = mysql_real_escape_string($value);
  }

Add POST data to SESSION

foreach ($_POST as $key => $val) {
$val = str_replace("\'", "`", $val);
$val = str_replace("\\", " ", $val);
$_SESSION[$key]=trim($val);
}

foreach ($_SESSION as $key => $val) {
$_SESSION[$key]=str_replace("\'", "`", $val);
$_SESSION[$key]=str_replace("\\", " ", $val);
}

Output buffering

ob_start();

echo "ABC ";
$out1 = ob_get_contents();

echo "XYZ";
$out2 = ob_get_contents();

ob_flush();
echo "
------------------
$out1,$out2";

Select all check boxes - Java script

function check_all(){
var x=document.getElementsByTagName("input");

for (i=0; i if (x[i].name=='chk_list[]'){
//x[i].style.display = 'none'; // hide checkbox
x[i].checked = 1; // to check checkbox
}
}
}