mini\Database\VirtualDatabase::createAggregate()
Method
public
Signature
public function createAggregate(string $name, callable $stepCallback, callable $finalCallback, int $argCount = -1): boolParameters
| Name | Type | Default | Description |
|---|---|---|---|
$name |
string |
required | Documentation missing |
$stepCallback |
callable |
required | Documentation missing |
$finalCallback |
callable |
required | Documentation missing |
$argCount |
int |
-1
|
Documentation missing |
Returns
bool
Documentation
Register a custom aggregate function
Similar to SQLite3::createAggregate. The step callback is called for each row with the current context and argument values. The final callback is called after all rows to produce the result.
// Example: Custom GROUP_CONCAT
$vdb->createAggregate(
'group_concat',
function(&$context, $value) {
$context[] = $value;
},
function(&$context) {
return implode(',', $context ?? []);
},
1
);