dbdelta [ WordPress Function ]
dbdelta ( $queries = '', $execute = true )
| Parameters: |
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| Returns: |
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| Defined at: |
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{@internal Missing Short Description}}
{@internal Missing Long Description}}
Source
<?php
function dbDelta( $queries = '', $execute = true ) {
global $wpdb;
if ( in_array( $queries, array( '', 'all', 'blog', 'global', 'ms_global' ), true ) )
$queries = wp_get_db_schema( $queries );
// Separate individual queries into an array
if ( !is_array($queries) ) {
$queries = explode( ';', $queries );
$queries = array_filter( $queries );
}
$queries = apply_filters( 'dbdelta_queries', $queries );
$cqueries = array(); // Creation Queries
$iqueries = array(); // Insertion Queries
$for_update = array();
// Create a tablename index for an array ($cqueries) of queries
foreach($queries as $qry) {
if (preg_match("|CREATE TABLE ([^ ]*)|", $qry, $matches)) {
$cqueries[ trim( $matches[1], '`' ) ] = $qry;
$for_update[$matches[1]] = 'Created table '.$matches[1];
} else if (preg_match("|CREATE DATABASE ([^ ]*)|", $qry, $matches)) {
array_unshift($cqueries, $qry);
} else if (preg_match("|INSERT INTO ([^ ]*)|", $qry, $matches)) {
$iqueries[] = $qry;
} else if (preg_match("|UPDATE ([^ ]*)|", $qry, $matches)) {
$iqueries[] = $qry;
} else {
// Unrecognized query type
}
}
$cqueries = apply_filters( 'dbdelta_create_queries', $cqueries );
$iqueries = apply_filters( 'dbdelta_insert_queries', $iqueries );
$global_tables = $wpdb->tables( 'global' );
foreach ( $cqueries as $table => $qry ) {
// Upgrade global tables only for the main site. Don't upgrade at all if DO_NOT_UPGRADE_GLOBAL_TABLES is defined.
if ( in_array( $table, $global_tables ) && ( !is_main_site() || defined( 'DO_NOT_UPGRADE_GLOBAL_TABLES' ) ) )
continue;
// Fetch the table column structure from the database
$wpdb->suppress_errors();
$tablefields = $wpdb->get_results("DESCRIBE {$table};");
$wpdb->suppress_errors( false );
if ( ! $tablefields )
continue;
// Clear the field and index arrays
$cfields = $indices = array();
// Get all of the field names in the query from between the parens
preg_match("|\((.*)\)|ms", $qry, $match2);
$qryline = trim($match2[1]);
// Separate field lines into an array
$flds = explode("\n", $qryline);
//echo "<hr/><pre>\n".print_r(strtolower($table), true).":\n".print_r($cqueries, true)."</pre><hr/>";
// For every field line specified in the query
foreach ($flds as $fld) {
// Extract the field name
preg_match("|^([^ ]*)|", trim($fld), $fvals);
$fieldname = trim( $fvals[1], '`' );
// Verify the found field name
$validfield = true;
switch (strtolower($fieldname)) {
case '':
case 'primary':
case 'index':
case 'fulltext':
case 'unique':
case 'key':
$validfield = false;
$indices[] = trim(trim($fld), ", \n");
break;
}
$fld = trim($fld);
// If it's a valid field, add it to the field array
if ($validfield) {
$cfields[strtolower($fieldname)] = trim($fld, ", \n");
}
}
// For every field in the table
foreach ($tablefields as $tablefield) {
// If the table field exists in the field array...
if (array_key_exists(strtolower($tablefield->Field), $cfields)) {
// Get the field type from the query
preg_match("|".$tablefield->Field." ([^ ]*( unsigned)?)|i", $cfields[strtolower($tablefield->Field)], $matches);
$fieldtype = $matches[1];
// Is actual field type different from the field type in query?
if ($tablefield->Type != $fieldtype) {
// Add a query to change the column type
$cqueries[] = "ALTER TABLE {$table} CHANGE COLUMN {$tablefield->Field} " . $cfields[strtolower($tablefield->Field)];
$for_update[$table.'.'.$tablefield->Field] = "Changed type of {$table}.{$tablefield->Field} from {$tablefield->Type} to {$fieldtype}";
}
// Get the default value from the array
//echo "{$cfields[strtolower($tablefield->Field)]}<br>";
if (preg_match("| DEFAULT '(.*)'|i", $cfields[strtolower($tablefield->Field)], $matches)) {
$default_value = $matches[1];
if ($tablefield->Default != $default_value) {
// Add a query to change the column's default value
$cqueries[] = "ALTER TABLE {$table} ALTER COLUMN {$tablefield->Field} SET DEFAULT '{$default_value}'";
$for_update[$table.'.'.$tablefield->Field] = "Changed default value of {$table}.{$tablefield->Field} from {$tablefield->Default} to {$default_value}";
}
}
// Remove the field from the array (so it's not added)
unset($cfields[strtolower($tablefield->Field)]);
} else {
// This field exists in the table, but not in the creation queries?
}
}
// For every remaining field specified for the table
foreach ($cfields as $fieldname => $fielddef) {
// Push a query line into $cqueries that adds the field to that table
$cqueries[] = "ALTER TABLE {$table} ADD COLUMN $fielddef";
$for_update[$table.'.'.$fieldname] = 'Added column '.$table.'.'.$fieldname;
}
// Index stuff goes here
// Fetch the table index structure from the database
$tableindices = $wpdb->get_results("SHOW INDEX FROM {$table};");
if ($tableindices) {
// Clear the index array
unset($index_ary);
// For every index in the table
foreach ($tableindices as $tableindex) {
// Add the index to the index data array
$keyname = $tableindex->Key_name;
$index_ary[$keyname]['columns'][] = array('fieldname' => $tableindex->Column_name, 'subpart' => $tableindex->Sub_part);
$index_ary[$keyname]['unique'] = ($tableindex->Non_unique == 0)?true:false;
}
// For each actual index in the index array
foreach ($index_ary as $index_name => $index_data) {
// Build a create string to compare to the query
$index_string = '';
if ($index_name == 'PRIMARY') {
$index_string .= 'PRIMARY ';
} else if($index_data['unique']) {
$index_string .= 'UNIQUE ';
}
$index_string .= 'KEY ';
if ($index_name != 'PRIMARY') {
$index_string .= $index_name;
}
$index_columns = '';
// For each column in the index
foreach ($index_data['columns'] as $column_data) {
if ($index_columns != '') $index_columns .= ',';
// Add the field to the column list string
$index_columns .= $column_data['fieldname'];
if ($column_data['subpart'] != '') {
$index_columns .= '('.$column_data['subpart'].')';
}
}
// Add the column list to the index create string
$index_string .= ' ('.$index_columns.')';
if (!(($aindex = array_search($index_string, $indices)) === false)) {
unset($indices[$aindex]);
//echo "<pre style=\"border:1px solid #ccc;margin-top:5px;\">{$table}:<br />Found index:".$index_string."</pre>\n";
}
//else echo "<pre style=\"border:1px solid #ccc;margin-top:5px;\">{$table}:<br /><b>Did not find index:</b>".$index_string."<br />".print_r($indices, true)."</pre>\n";
}
}
// For every remaining index specified for the table
foreach ( (array) $indices as $index ) {
// Push a query line into $cqueries that adds the index to that table
$cqueries[] = "ALTER TABLE {$table} ADD $index";
$for_update[$table.'.'.$fieldname] = 'Added index '.$table.' '.$index;
}
// Remove the original table creation query from processing
unset( $cqueries[ $table ], $for_update[ $table ] );
}
$allqueries = array_merge($cqueries, $iqueries);
if ($execute) {
foreach ($allqueries as $query) {
//echo "<pre style=\"border:1px solid #ccc;margin-top:5px;\">".print_r($query, true)."</pre>\n";
$wpdb->query($query);
}
}
return $for_update;
}
?>
Examples [ wp-snippets.com ]
Top Google zoekresultaten
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Gebruikersdiscussies [ wordpress.org ]
- yobikwhatus on "dbDelta: Issues with upgrading tables with composite primary key"
- James Collins on "dbDelta: Issues with upgrading tables with composite primary key"
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- theBrettman on "Can't create table during activation..."
- theBrettman on "Can't create table during activation..."
- yobikwhatus on "dbDelta: Issues with upgrading tables with composite primary key"
- chibib0 on "dbDelta alternative?? a sql query with a semicolon problem"
- Peter Baylies on "dbDelta alternative?? a sql query with a semicolon problem"
- chibib0 on "dbDelta alternative?? a sql query with a semicolon problem"
