->count() -- Perform a select count() request
Description
It performs a select count() request on the tables key
column and returns the number of resulting rows.
The default condition applied to the count() is
a combination of the object variables and whereAdd settings. If
the constant DB_DATAOBJECT_WHEREADD_ONLY is passed in as the first
parameter then only the whereAdd settings will be used.
Parameter
string $countWhat - by default count will count on the primary key,
if you need to count something else, if you just say DISTINCT,
it will count the primiary key prefixed with distinct, or put your own value in
(don't forget to escape it if necessary)
boolean $useWhereAddOnly - use only the
whereAdd conditions (by default, count will only use both the object settings and
the whereAdd conditions)
Return value
int|false - number of results or false on an error
Note
This function can not be called
statically.
Example
Example 39-1. Various examples of using count()
<?php
/* using property values */
$person = new DataObjects_Person;
$person->name = "test"
$total = $person->count();
echo "There are {$total} people with a name like test";
/* using countWhat */
$person = new DataObjects_Person;
$total = $person->count('DISTINCT name');
echo "There are {$total} names in the database";
/* using countWhat value = DISTINCT */
$person = new DataObjects_Person;
$total = $person->count('DISTINCT');
echo "There are {$total} names in the database";
/* using whereOnly */
$person = new DataObjects_Person;
$person->name = "test";
$person->whereAdd("name like '%test%'");
$total = $person->count(DB_DATAOBJECT_WHEREADD_ONLY);
echo "There are {$total} names in the database";
?>
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Example 39-2. Resulting SQL SELECT count(person.id) AS DATAOBJECT_NUM
FROM person
WHERE person.name = 'test';
SELECT count(DISTINCT name) AS DATAOBJECT_NUM
FROM person;
SELECT count(DISTINCT person.id) AS DATAOBJECT_NUM
FROM person;
SELECT count(person.id) AS DATAOBJECT_NUM
FROM person
WHERE name like '%test%'; |
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