Metadata
A MariaDB result set contains metadata. The metadata describes the columns found in the result set. All metadata send by MariaDB is accessible through the mysqli interface. The extension performs no or negligible changes to the information it receives. Differences between MariaDB server versions are not aligned.
Meta data is access through the mysqli_result interface.
Example 20.97. Accessing result set meta data
<?php
$mysqli = new mysqli('example.com', 'user', 'password', 'database');
if ($mysqli->connect_errno) {
echo 'Failed to connect to MySQL: (' . $mysqli->connect_errno . ') ' . $mysqli->connect_error;
}
$res = $mysqli->query('SELECT 1 AS _one, 'Hello' AS _two FROM DUAL');
var_dump($res->fetch_fields());
?>
The above example will output:
array(2) {
[0]=>
object(stdClass)#3 (13) {
['name']=>
string(4) '_one'
['orgname']=>
string(0) ''
['table']=>
string(0) ''
['orgtable']=>
string(0) ''
['def']=>
string(0) ''
['db']=>
string(0) ''
['catalog']=>
string(3) 'def'
['max_length']=>
int(1)
['length']=>
int(1)
['charsetnr']=>
int(63)
['flags']=>
int(32897)
['type']=>
int(8)
['decimals']=>
int(0)
}
[1]=>
object(stdClass)#4 (13) {
['name']=>
string(4) '_two'
['orgname']=>
string(0) ''
['table']=>
string(0) ''
['orgtable']=>
string(0) ''
['def']=>
string(0) ''
['db']=>
string(0) ''
['catalog']=>
string(3) 'def'
['max_length']=>
int(5)
['length']=>
int(5)
['charsetnr']=>
int(8)
['flags']=>
int(1)
['type']=>
int(253)
['decimals']=>
int(31)
}
}
Prepared statements
Meta data of result sets created using prepared statements are accessed the same way. A suitable mysqli_result handle is returned by mysqli_stmt_result_metadata.
Example 20.98. Prepared statements metadata
<?php
$stmt = $mysqli->prepare('SELECT 1 AS _one, 'Hello' AS _two FROM DUAL');
$stmt->execute();
$res = $stmt->result_metadata();
var_dump($res->fetch_fields());
?>
See also
mysqli::query
|
mysqli_result::fetch_fields |