wppaste
WordPress

wpdb::get_results( string $query = null, string $output = OBJECT ): array|object|null

Since
0.71
Source
wp-includes/class-wpdb.php:3148
Retrieves an entire SQL result set from the database (i.e., many rows).

Description

Executes a SQL query and returns the entire SQL result.

Compatibility

WordPress
since 0.71
PHP
7.4–8.6-dev
  • 6.7.7
  • 6.8.8
  • 6.9.7
  • 7.0.4
  • 7.1.0

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$querystringoptional
SQL query.Default: null
$outputstringoptional
Any of ARRAY_A | ARRAY_N | OBJECT | OBJECT_K constants.
With one of the first three, return an array of rows indexed from 0 by SQL result row number. Each row is an associative array (column => value, ...), a numerically indexed array (0 => value, ...), or an object ( ->column = value ), respectively. With OBJECT_K, return an associative array of row objects keyed by the value of each row's first column's value. Duplicate keys are discarded.
Default OBJECT.Default: OBJECT

Return value

array|object|null
Database query results.

Performance profile

How much work a call to wpdb::get_results() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class
Heavy

Reaches the database via wpdb::get_results().

Scaling
Scales with input

The body loops, so the work grows with what you pass in.

Instructions
11–46

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 99.

Plugin surface
None

Nothing here hands control to plugin code.

Called by
1

1 place in core call this, so the cost is paid more often than your own code shows.

What it touches

  • sqldatabase querywpdb::get_results()this function does it

What one call costs · 5 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wpdb::get_results() can have, taken from its control-flow graph on PHP 8.5.

WhenInstructionsCalls it makes
always11none
$output === false22–40->query()
$output === false26–46->check_safe_collation(), ->query()
$output !== false36–37->query(), strtoupper()
$output !== false40–43->check_safe_collation(), ->query(), strtoupper()

Across PHP versions

Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 99 instructions, 11–46 executed per call, 18 branches. The work does not change between versions.

An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.

Uses · 2

Used by · 1

Source code

	public function get_results( $query = null, $output = OBJECT ) {		$this->func_call = "\$db->get_results(\"$query\", $output)"; 		if ( $query ) {			if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {				$this->check_current_query = false;			} 			$this->query( $query );		} else {			return null;		} 		$new_array = array();		if ( OBJECT === $output ) {			// Return an integer-keyed array of row objects.			return $this->last_result;		} elseif ( OBJECT_K === $output ) {			/*			 * Return an array of row objects with keys from column 1.			 * (Duplicates are discarded.)			 */			if ( $this->last_result ) {				foreach ( $this->last_result as $row ) {					$var_by_ref = get_object_vars( $row );					$key        = array_shift( $var_by_ref );					if ( ! isset( $new_array[ $key ] ) ) {						$new_array[ $key ] = $row;					}				}			}			return $new_array;		} elseif ( ARRAY_A === $output || ARRAY_N === $output ) {			// Return an integer-keyed array of...			if ( $this->last_result ) {				if ( ARRAY_N === $output ) {					foreach ( (array) $this->last_result as $row ) {						// ...integer-keyed row arrays.						$new_array[] = array_values( get_object_vars( $row ) );					}				} else {					foreach ( (array) $this->last_result as $row ) {						// ...column name-keyed row arrays.						$new_array[] = get_object_vars( $row );					}				}			}			return $new_array;		} elseif ( strtoupper( $output ) === OBJECT ) {			// Back compat for OBJECT being previously case-insensitive.			return $this->last_result;		}		return null;	}

Changelog

Introduced in 0.71. 2 changes between 6.7.7 and 7.1.0.

  1. 6.7.7
  2. 6.8.8
  3. 6.9.7
  4. 7.0.4
  5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

7.1.0
Parameter $query retyped from string to string|null.verified against source
7.1.0
Return type changed from array|object|null to array|null.verified against source
0.71
Introduced.from the docblock

About this page

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