/**
*
* This allows the cached values for a table's field list to be erased.
* If $tablename is empty, then the whole cache is erased.
*
* @param string $tableName
*
* @return boolean
*/
function clearCachedFieldlist($tableName = false)
{
if ($tableName != false) {
unset(self::$cached_fieldlists[$tableName]);
} else {
self::$cached_fieldlists = array();
}
return true;
}
/**
*
* @param string $tableName
* @param array $partitions
* @param array $indexes
* @param array $extensions
*/
public function createOrReplacePartition($tableName, $partitions, $indexes, $extensions)
{
//We need the plpgsql language to be installed for this to work:
$this->createLanguage('plpgsql');
$trigger = 'CREATE OR REPLACE FUNCTION ' . $tableName . '_insert_trigger() RETURNS TRIGGER AS $$ BEGIN ';
$first = true;
//Do we need to create a tablespace for this item?
if ($extensions && isset($extensions['tablespace'])) {
$this->createOrReplaceTablespace($extensions['tablespace']['name'], $extensions['tablespace']['location']);
$tableSpace = ' TABLESPACE ' . $extensions['tablespace']['name'];
} else {
$tableSpace = '';
}
foreach ($partitions as $partition_name => $partition_value) {
//Check that this child table does not already exist:
if (!$this->hasTable($partition_name)) {
$this->query("CREATE TABLE \"{$partition_name}\" (CHECK (" . str_replace('NEW.', '', $partition_value) . ")) INHERITS (\"{$tableName}\"){$tableSpace};");
} else {
//Drop the constraint, we will recreate in in the next line
$existing_constraint = $this->preparedQuery("SELECT conname FROM pg_constraint WHERE conname = ?;", array("{$partition_name}_pkey"));
if ($existing_constraint) {
$this->query("ALTER TABLE \"{$partition_name}\" DROP CONSTRAINT \"{$partition_name}_pkey\";");
}
$this->dropTrigger(strtolower('trigger_' . $tableName . '_insert'), $tableName);
}
$this->query("ALTER TABLE \"{$partition_name}\" ADD CONSTRAINT \"{$partition_name}_pkey\" PRIMARY KEY (\"ID\");");
if ($first) {
$trigger .= 'IF';
$first = false;
} else {
$trigger .= 'ELSIF';
}
$trigger .= " ({$partition_value}) THEN INSERT INTO \"{$partition_name}\" VALUES (NEW.*);";
if ($indexes) {
// We need to propogate the indexes through to the child pages.
// Some of this code is duplicated, and could be tidied up
foreach ($indexes as $name => $this_index) {
if ($this_index['type'] == 'fulltext') {
$fillfactor = $where = '';
if (isset($this_index['fillfactor'])) {
$fillfactor = 'WITH (FILLFACTOR = ' . $this_index['fillfactor'] . ')';
}
if (isset($this_index['where'])) {
$where = 'WHERE ' . $this_index['where'];
}
$clusterMethod = PostgreSQLDatabase::default_fts_cluster_method();
$this->query("CREATE INDEX \"" . $this->buildPostgresIndexName($partition_name, $this_index['name']) . "\" ON \"" . $partition_name . "\" USING {$clusterMethod}(\"ts_" . $name . "\") {$fillfactor} {$where}");
$ts_details = $this->fulltext($this_index, $partition_name, $name);
$this->query($ts_details['triggers']);
} else {
if (is_array($this_index)) {
$index_name = $this_index['name'];
} else {
$index_name = trim($this_index, '()');
}
$createIndex = $this->getIndexSqlDefinition($partition_name, $index_name, $this_index);
if ($createIndex !== false) {
$this->query($createIndex);
}
}
}
}
//Lastly, clustering goes here:
if ($extensions && isset($extensions['cluster'])) {
$this->query("CLUSTER \"{$partition_name}\" USING \"{$extensions['cluster']}\";");
}
}
$trigger .= 'ELSE RAISE EXCEPTION \'Value id out of range. Fix the ' . $tableName . '_insert_trigger() function!\'; END IF; RETURN NULL; END; $$ LANGUAGE plpgsql;';
$trigger .= 'CREATE TRIGGER trigger_' . $tableName . '_insert BEFORE INSERT ON "' . $tableName . '" FOR EACH ROW EXECUTE PROCEDURE ' . $tableName . '_insert_trigger();';
$this->query($trigger);
}