1<?php
2/**
3 * Plugins may load this file to gain access to special helper functions
4 * for plugin installation. This file is not included by WordPress and it is
5 * recommended, to prevent fatal errors, that this file is included using
6 * require_once.
7 *
8 * These functions are not optimized for speed, but they should only be used
9 * once in a while, so speed shouldn't be a concern. If it is and you are
10 * needing to use these functions a lot, you might experience timeouts.
11 * If you do, then it is advised to just write the SQL code yourself.
12 *
13 * check_column( 'wp_links', 'link_description', 'mediumtext' );
14 *
15 * if ( check_column( $wpdb->comments, 'comment_author', 'tinytext' ) ) {
16 * echo "ok\n";
17 * }
18 *
19 * // Check the column.
20 * if ( ! check_column( $wpdb->links, 'link_description', 'varchar( 255 )' ) ) {
21 * $ddl = "ALTER TABLE $wpdb->links MODIFY COLUMN link_description varchar(255) NOT NULL DEFAULT '' ";
22 * $q = $wpdb->query( $ddl );
23 * }
24 *
25 * $error_count = 0;
26 * $tablename = $wpdb->links;
27 *
28 * if ( check_column( $wpdb->links, 'link_description', 'varchar( 255 )' ) ) {
29 * $res .= $tablename . ' - ok <br />';
30 * } else {
31 * $res .= 'There was a problem with ' . $tablename . '<br />';
32 * ++$error_count;
33 * }
34 *
35 * @package WordPress
36 * @subpackage Plugin
37 */
38
39/** Load WordPress Bootstrap */
40require_once dirname( __DIR__ ) . '/wp-load.php';
41
42if ( ! function_exists( 'maybe_create_table' ) ) :
43 /**
44 * Creates a table in the database if it doesn't already exist.
45 *
46 * @since 1.0.0
47 *
48 * @global wpdb $wpdb WordPress database abstraction object.
49 *
50 * @param string $table_name Database table name.
51 * @param string $create_ddl SQL statement to create table.
52 * @return bool True on success or if the table already exists. False on failure.
53 */
54 function maybe_create_table( $table_name, $create_ddl ) {
55 global $wpdb;
56
57 foreach ( $wpdb->get_col( 'SHOW TABLES', 0 ) as $table ) {
58 if ( $table === $table_name ) {
59 return true;
60 }
61 }
62
63 // Didn't find it, so try to create it.
64 // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- No applicable variables for this query.
65 $wpdb->query( $create_ddl );
66
67 // We cannot directly tell whether this succeeded!
68 foreach ( $wpdb->get_col( 'SHOW TABLES', 0 ) as $table ) {
69 if ( $table === $table_name ) {
70 return true;
71 }
72 }
73
74 return false;
75 }
76endif;
77
78if ( ! function_exists( 'maybe_add_column' ) ) :
79 /**
80 * Adds column to database table, if it doesn't already exist.
81 *
82 * @since 1.0.0
83 *
84 * @global wpdb $wpdb WordPress database abstraction object.
85 *
86 * @param string $table_name Database table name.
87 * @param string $column_name Table column name.
88 * @param string $create_ddl SQL statement to add column.
89 * @return bool True on success or if the column already exists. False on failure.
90 */
91 function maybe_add_column( $table_name, $column_name, $create_ddl ) {
92 global $wpdb;
93
94 // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names.
95 foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) {
96 if ( $column === $column_name ) {
97 return true;
98 }
99 }
100
101 // Didn't find it, so try to create it.
102 // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- No applicable variables for this query.
103 $wpdb->query( $create_ddl );
104
105 // We cannot directly tell whether this succeeded!
106 // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names.
107 foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) {
108 if ( $column === $column_name ) {
109 return true;
110 }
111 }
112
113 return false;
114 }
115endif;
116
117/**
118 * Drops column from database table, if it exists.
119 *
120 * @since 1.0.0
121 *
122 * @global wpdb $wpdb WordPress database abstraction object.
123 *
124 * @param string $table_name Database table name.
125 * @param string $column_name Table column name.
126 * @param string $drop_ddl SQL statement to drop column.
127 * @return bool True on success or if the column doesn't exist. False on failure.
128 */
129function maybe_drop_column( $table_name, $column_name, $drop_ddl ) {
130 global $wpdb;
131
132 // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names.
133 foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) {
134 if ( $column === $column_name ) {
135
136 // Found it, so try to drop it.
137 // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- No applicable variables for this query.
138 $wpdb->query( $drop_ddl );
139
140 // We cannot directly tell whether this succeeded!
141 // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names.
142 foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) {
143 if ( $column === $column_name ) {
144 return false;
145 }
146 }
147 }
148 }
149
150 // Else didn't find it.
151 return true;
152}
153
154/**
155 * Checks that database table column matches the criteria.
156 *
157 * Uses the SQL DESC for retrieving the table info for the column. It will help
158 * understand the parameters, if you do more research on what column information
159 * is returned by the SQL statement. Pass in null to skip checking that criteria.
160 *
161 * Column names returned from DESC table are case sensitive and are as listed:
162 *
163 * - Field
164 * - Type
165 * - Null
166 * - Key
167 * - Default
168 * - Extra
169 *
170 * @since 1.0.0
171 *
172 * @global wpdb $wpdb WordPress database abstraction object.
173 *
174 * @param string $table_name Database table name.
175 * @param string $col_name Table column name.
176 * @param string $col_type Table column type.
177 * @param bool $is_null Optional. Check is null.
178 * @param mixed $key Optional. Key info.
179 * @param mixed $default_value Optional. Default value.
180 * @param mixed $extra Optional. Extra value.
181 * @return bool True, if matches. False, if not matching.
182 */
183function check_column( $table_name, $col_name, $col_type, $is_null = null, $key = null, $default_value = null, $extra = null ) {
184 global $wpdb;
185
186 $diffs = 0;
187
188 // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names.
189 $results = $wpdb->get_results( "DESC $table_name" );
190
191 foreach ( $results as $row ) {
192
193 if ( $row->Field === $col_name ) {
194
195 // Got our column, check the params.
196 if ( ( null !== $col_type ) && ( $row->Type !== $col_type ) ) {
197 ++$diffs;
198 }
199 if ( ( null !== $is_null ) && ( $row->Null !== $is_null ) ) {
200 ++$diffs;
201 }
202 if ( ( null !== $key ) && ( $row->Key !== $key ) ) {
203 ++$diffs;
204 }
205 if ( ( null !== $default_value ) && ( $row->Default !== $default_value ) ) {
206 ++$diffs;
207 }
208 if ( ( null !== $extra ) && ( $row->Extra !== $extra ) ) {
209 ++$diffs;
210 }
211
212 if ( $diffs > 0 ) {
213 return false;
214 }
215
216 return true;
217 } // End if found our column.
218 }
219
220 return false;
221}
222