Source

File: wp-includes/wp-db.php

public function tables( $scope = 'all', $prefix = true, $blog_id = 0 ) {
		switch ( $scope ) {
			case 'all':
				$tables = array_merge( $this->global_tables, $this->tables );
				if ( is_multisite() ) {
					$tables = array_merge( $tables, $this->ms_global_tables );
				}
				break;
			case 'blog':
				$tables = $this->tables;
				break;
			case 'global':
				$tables = $this->global_tables;
				if ( is_multisite() ) {
					$tables = array_merge( $tables, $this->ms_global_tables );
				}
				break;
			case 'ms_global':
				$tables = $this->ms_global_tables;
				break;
			case 'old':
				$tables = $this->old_tables;
				break;
			default:
				return array();
		}

		if ( $prefix ) {
			if ( ! $blog_id ) {
				$blog_id = $this->blogid;
			}
			$blog_prefix   = $this->get_blog_prefix( $blog_id );
			$base_prefix   = $this->base_prefix;
			$global_tables = array_merge( $this->global_tables, $this->ms_global_tables );
			foreach ( $tables as $k => $table ) {
				if ( in_array( $table, $global_tables, true ) ) {
					$tables[ $table ] = $base_prefix . $table;
				} else {
					$tables[ $table ] = $blog_prefix . $table;
				}
				unset( $tables[ $k ] );
			}

			if ( isset( $tables['users'] ) && defined( 'CUSTOM_USER_TABLE' ) ) {
				$tables['users'] = CUSTOM_USER_TABLE;
			}

			if ( isset( $tables['usermeta'] ) && defined( 'CUSTOM_USER_META_TABLE' ) ) {
				$tables['usermeta'] = CUSTOM_USER_META_TABLE;
			}
		}

		return $tables;
	}