MDB_Common::queryCol()

MDB_Common::queryCol() -- Fetch a single column

Synopsis

require_once 'MDB.php';

array &queryCol (string $query, string [$type = NULL], mixed [$colnum = 0])

Description

Fetch a single column from a result set of a query. The function takes care of doing the query and freeing the results when finished.

Parameter

string $query

the SQL query

string $type

if supplied, the type of the column in the result set will be set for fetching

array $params

if supplied, prepareQuery()/ executeQuery() will be used with this array as execute parameters

array $param_types

if supplied, the values in $param will automatically set to the passed datatypes

mixed $colnum

which column to return (integer [column number, starting at 0] or string [column name])

Return value

array - the first row of results as an array indexed from 0 or a MDB_Error, if fail

Throws

Table 26-1. Possible PEAR_Error values

Error codeError messageReasonSolution
MDB_ERROR_NO_DB_SELECTED NULL No database was choosen. Check the DSN in connect() .
MDB_ERROR_TRUNCATED NULL The result set contains fewer then two columns Check the SQL query or choose another query*() function
every other error code  Database specific error Check the database related section of PHP-Manual to detect the reason for this error. In the most cases a misformed SQL statment. Ie. using LIMIT in a SQL-Statment for an Oracle database.

Note

This function can not be called statically.

See

query() , limitQuery() , prepareQuery() , executeQuery() , queryRow() , queryOne() , queryAll()