3 * @copyright Copyright (C) 2010-2023, the Friendica project
5 * @license GNU AGPL version 3 or any later version
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU Affero General Public License as
9 * published by the Free Software Foundation, either version 3 of the
10 * License, or (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU Affero General Public License for more details.
17 * You should have received a copy of the GNU Affero General Public License
18 * along with this program. If not, see <https://www.gnu.org/licenses/>.
22 namespace Friendica\Util\Writer;
24 use Friendica\Database\Definition\ViewDefinition;
27 * SQL writer utility for the db view definition
29 class ViewDefinitionSqlWriter
32 * Creates a complete SQL definition bases on a give View Definition class
34 * @param ViewDefinition $definition The View definition class
36 * @return string The SQL definition as a string
38 public static function create(ViewDefinition $definition): string
42 foreach ($definition->getAll() as $viewName => $viewStructure) {
44 $sqlString .= "-- VIEW $viewName\n";
46 $sqlString .= static::dropView($viewName);
47 $sqlString .= static::createView($viewName, $viewStructure);
54 * Creates the SQL definition to drop a view
56 * @param string $viewName the view name
58 * @return string The SQL definition
60 public static function dropView(string $viewName): string
62 return sprintf("DROP VIEW IF EXISTS `%s`", static::escape($viewName)) . ";\n";
66 * Creates the SQL definition to create a new view
68 * @param string $viewName The view name
69 * @param array $viewStructure The structure information of the view
71 * @return string The SQL definition
73 public static function createView(string $viewName, array $viewStructure): string
76 foreach ($viewStructure['fields'] as $fieldname => $origin) {
77 if (is_string($origin)) {
78 $sql_rows[] = $origin . " AS `" . static::escape($fieldname) . "`";
79 } elseif (is_array($origin) && (sizeof($origin) == 2)) {
80 $sql_rows[] = "`" . static::escape($origin[0]) . "`.`" . static::escape($origin[1]) . "` AS `" . static::escape($fieldname) . "`";
83 return sprintf("CREATE VIEW `%s` AS SELECT \n\t", static::escape($viewName)) .
84 implode(",\n\t", $sql_rows) . "\n\t" . $viewStructure['query'] . ";\n\n";
88 * Standard escaping for SQL definitions
90 * @param string $sqlString the SQL string to escape
92 * @return string escaped SQL string
94 public static function escape(string $sqlString): string
96 return str_replace("'", "\\'", $sqlString);