**CONDITIONALS** are operators which allow you to get more specific (or general) in your query.

* \=\: equals
* \<\: less than
* \>\: greater than
* \<=\: less than or equal to
* \>=\: greater than or equal to
* \!=\: not equal to
* IS NOT NULL: has any value
* IS NULL: has no value at all
* BETWEEN: within a specified range
* NOT BETWEEN: outside of a specified range
* OR: one of two equations are true
* ||: same as OR
* AND: both equations are true
* &&: same as AND
* NOT: both equations are false
* !: same as NOT

<Code
  language="php"
  text={`$sql = mysql_query("SELECT * FROM table_name WHERE some equation && another equation");

while ($row = mysql_fetch_row($sql)) {
echo "$row[0] $row[1] $row[2] <br />";
}`}
/>

The query will only pick out the rows that provide a TRUE result according to the WHERE equation. In this case, there would be TWO parts that must be true to return a result. Example...

<Code
  language="php"
  text={`$sql = mysql_query("SELECT * FROM address_book WHERE first_name='David' && last_name='Stanley'");

while ($row = mysql_fetch_row($sql)) {
echo "$row[0] $row[1] $row[2] <br />";
}`}
/>

The query would search the address_book table and compare all of the data in the first_name column AND the last_name column for the specified values. The WHILE loop then prints out the results found if both equations are found TRUE.

Learn about how to use conditionals in MySQL.

CONDITIONALS

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