schema.inc

1. 7.x includes/database/sqlite/schema.inc
2. 7.x includes/database/mysql/schema.inc
3. 7.x includes/database/schema.inc

1. 9 core/includes/schema.inc
2. 8.9.x core/includes/schema.inc

<?php

/**
 * @file
 * Database schema code for PostgreSQL database servers.
 */


/**
 * @ingroup schemaapi
 * @{
 */
class DatabaseSchema_pgsql  extends DatabaseSchema {
 
 /**
 * PostgreSQL's temporary namespace name.
 *
 * @var string
 */
 protected $tempNamespaceName;
 
 /**
 * A cache of information about blob columns and sequences of tables.
 *
 * This is collected by DatabaseConnection_pgsql->queryTableInformation(),
 * by introspecting the database.
 *
 * @see DatabaseConnection_pgsql->queryTableInformation()
 * @var array
 */
 protected $tableInformation = array();
 
 /**
 * The maximum allowed length for index, primary key and constraint names.
 *
 * Value will usually be set to a 63 chars limit but PostgreSQL allows
 * to higher this value before compiling, so we need to check for that.
 *
 * @var int
 */
 protected $maxIdentifierLength;
 
 /**
 * Make sure to limit identifiers according to PostgreSQL compiled in length.
 *
 * PostgreSQL allows in standard configuration identifiers no longer than 63
 * chars for table/relation names, indexes, primary keys, and constraints. So
 * we map all identifiers that are too long to drupal_base64hash_tag, where
 * tag is one of:
 * - idx for indexes
 * - key for constraints
 * - pkey for primary keys
 * - seq for sequences
 *
 * @param string $table_identifier_part
 * The first argument used to build the identifier string. This usually
 * refers to a table/relation name.
 * @param string $column_identifier_part
 * The second argument used to build the identifier string. This usually
 * refers to one or more column names.
 * @param string $tag
 * The identifier tag. It can be one of 'idx', 'key', 'pkey' or 'seq'.
 *
 * @return string
 * The index/constraint/pkey identifier.
 */
 protected function ensureIdentifiersLength($table_identifier_part, $column_identifier_part, $tag) {
 $info = $this->getPrefixInfo($table_identifier_part);
 $table_identifier_part = $info['table'];
 // Filters out potentially empty $column_identifier_part to ensure
 // compatibility with old naming convention (see prefixNonTable()).
 $identifiers = array_filter (array(
 $table_identifier_part,
 $column_identifier_part,
 $tag,
 ));
 $identifierName = implode ('_', $identifiers);
 // Retrieve the max identifier length which is usually 63 characters
 // but can be altered before PostgreSQL is compiled so we need to check.
 if (empty($this->maxIdentifierLength)) {
 $this->maxIdentifierLength = $this->connection
 ->query ("SHOW max_identifier_length")
 ->fetchField ();
 }
 if (strlen ($identifierName) > $this->maxIdentifierLength) {
 $saveIdentifier = 'drupal_' . $this->hashBase64($identifierName) . '_' . $tag;
 }
 else {
 $saveIdentifier = $identifierName;
 }
 return $saveIdentifier;
 }
 
 /**
 * Fetch the list of blobs and sequences used on a table.
 *
 * We introspect the database to collect the information required by insert
 * and update queries.
 *
 * @param $table_name
 * The non-prefixed name of the table.
 * @return
 * An object with two member variables:
 * - 'blob_fields' that lists all the blob fields in the table.
 * - 'sequences' that lists the sequences used in that table.
 */
 public function queryTableInformation($table) {
 // Generate a key to reference this table's information on.
 $key = $this->connection
 ->prefixTables ('{' . $table . '}');
 // Take into account that temporary tables are stored in a different schema.
 // \DatabaseConnection::generateTemporaryTableName() sets 'db_temporary_'
 // prefix to all temporary tables.
 if (strpos ($key, '.') === FALSE && strpos ($table, 'db_temporary_') === FALSE) {
 $key = 'public.' . $key;
 }
 else {
 $key = $this->getTempNamespaceName() . '.' . $key;
 }
 if (!isset($this->tableInformation[$key])) {
 $table_information = (object) array(
 'blob_fields' => array(),
 'sequences' => array(),
 );
 // The bytea columns and sequences for a table can be found in
 // pg_attribute, which is significantly faster than querying the
 // information_schema. The data type of a field can be found by lookup
 // of the attribute ID, and the default value must be extracted from the
 // node tree for the attribute definition instead of the historical
 // human-readable column, adsrc.
 $sql = <<<'EOD'
 SELECT pg_attribute.attname AS column_name, format_type(pg_attribute.atttypid, pg_attribute.atttypmod) AS data_type, pg_get_expr(pg_attrdef.adbin, pg_attribute.attrelid) AS column_default
 FROM pg_attribute
 LEFT JOIN pg_attrdef ON pg_attrdef.adrelid = pg_attribute.attrelid AND pg_attrdef.adnum = pg_attribute.attnum
 WHERE pg_attribute.attnum > 0
 AND NOT pg_attribute.attisdropped
 AND pg_attribute.attrelid = :key::regclass
 AND (format_type(pg_attribute.atttypid, pg_attribute.atttypmod) = 'bytea'
 OR pg_get_expr(pg_attrdef.adbin, pg_attribute.attrelid) LIKE 'nextval%')
 EOD;
 $result = $this->connection
 ->query ($sql, array(
 ':key' => $key,
 ));
 if (empty($result)) {
 return $table_information;
 }
 foreach ($result as $column) {
 if ($column->data_type == 'bytea') {
 $table_information->blob_fields[$column->column_name] = TRUE;
 }
 elseif (preg_match ("/nextval\\('([^']+)'/", $column->column_default, $matches)) {
 // We must know of any sequences in the table structure to help us
 // return the last insert id. If there is more than 1 sequences the
 // first one (index 0 of the sequences array) will be used.
 $table_information->sequences[] = $matches[1];
 $table_information->serial_fields[] = $column->column_name;
 }
 }
 $this->tableInformation[$key] = $table_information;
 }
 return $this->tableInformation[$key];
 }
 
 /**
 * Gets PostgreSQL's temporary namespace name.
 *
 * @return string
 * PostgreSQL's temporary namespace anme.
 */
 protected function getTempNamespaceName() {
 if (!isset($this->tempNamespaceName)) {
 $this->tempNamespaceName = $this->connection
 ->query ('SELECT nspname FROM pg_namespace WHERE oid = pg_my_temp_schema()')
 ->fetchField ();
 }
 return $this->tempNamespaceName;
 }
 
 /**
 * Fetch the list of CHECK constraints used on a field.
 *
 * We introspect the database to collect the information required by field
 * alteration.
 *
 * @param $table
 * The non-prefixed name of the table.
 * @param $field
 * The name of the field.
 * @return
 * An array of all the checks for the field.
 */
 public function queryFieldInformation($table, $field) {
 $prefixInfo = $this->getPrefixInfo($table, TRUE);
 // Split the key into schema and table for querying.
 $schema = $prefixInfo['schema'];
 $table_name = $prefixInfo['table'];
 $field_information = (object) array(
 'checks' => array(),
 );
 $checks = $this->connection
 ->query ("SELECT conname FROM pg_class cl INNER JOIN pg_constraint co ON co.conrelid = cl.oid INNER JOIN pg_attribute attr ON attr.attrelid = cl.oid AND attr.attnum = ANY (co.conkey) INNER JOIN pg_namespace ns ON cl.relnamespace = ns.oid WHERE co.contype = 'c' AND ns.nspname = :schema AND cl.relname = :table AND attr.attname = :column", array(
 ':schema' => $schema,
 ':table' => $table_name,
 ':column' => $field,
 ));
 $field_information = $checks->fetchCol ();
 return $field_information;
 }
 
 /**
 * Generate SQL to create a new table from a Drupal schema definition.
 *
 * @param $name
 * The name of the table to create.
 * @param $table
 * A Schema API table definition array.
 * @return
 * An array of SQL statements to create the table.
 */
 protected function createTableSql($name, $table) {
 $sql_fields = array();
 foreach ($table['fields'] as $field_name => $field) {
 $sql_fields[] = $this->createFieldSql($field_name, $this->processField($field));
 }
 $sql_keys = array();
 if (isset($table['primary key']) && is_array ($table['primary key'])) {
 $sql_keys[] = 'CONSTRAINT ' . $this->ensureIdentifiersLength($name, '', 'pkey') . ' PRIMARY KEY (' . implode (', ', $table['primary key']) . ')';
 }
 if (isset($table['unique keys']) && is_array ($table['unique keys'])) {
 foreach ($table['unique keys'] as $key_name => $key) {
 $sql_keys[] = 'CONSTRAINT ' . $this->ensureIdentifiersLength($name, $key_name, 'key') . ' UNIQUE (' . implode (', ', $key) . ')';
 }
 }
 $sql = "CREATE TABLE {" . $name . "} (\n\t";
 $sql .= implode (",\n\t", $sql_fields);
 if (count ($sql_keys) > 0) {
 $sql .= ",\n\t";
 }
 $sql .= implode (",\n\t", $sql_keys);
 $sql .= "\n)";
 $statements[] = $sql;
 if (isset($table['indexes']) && is_array ($table['indexes'])) {
 foreach ($table['indexes'] as $key_name => $key) {
 $statements[] = $this->_createIndexSql($name, $key_name, $key);
 }
 }
 // Add table comment.
 if (!empty($table['description'])) {
 $statements[] = 'COMMENT ON TABLE {' . $name . '} IS ' . $this->prepareComment($table['description']);
 }
 // Add column comments.
 foreach ($table['fields'] as $field_name => $field) {
 if (!empty($field['description'])) {
 $statements[] = 'COMMENT ON COLUMN {' . $name . '}.' . $field_name . ' IS ' . $this->prepareComment($field['description']);
 }
 }
 return $statements;
 }
 
 /**
 * Create an SQL string for a field to be used in table creation or
 * alteration.
 *
 * Before passing a field out of a schema definition into this
 * function it has to be processed by _db_process_field().
 *
 * @param $name
 * Name of the field.
 * @param $spec
 * The field specification, as per the schema data structure format.
 */
 protected function createFieldSql($name, $spec) {
 $sql = $name . ' ' . $spec['pgsql_type'];
 if (isset($spec['type']) && $spec['type'] == 'serial') {
 unset($spec['not null']);
 }
 if (in_array ($spec['pgsql_type'], array(
 'varchar',
 'character',
 'text',
 )) && isset($spec['length'])) {
 $sql .= '(' . $spec['length'] . ')';
 }
 elseif (isset($spec['precision']) && isset($spec['scale'])) {
 $sql .= '(' . $spec['precision'] . ', ' . $spec['scale'] . ')';
 }
 if (!empty($spec['unsigned'])) {
 $sql .= " CHECK ({$name} >= 0)";
 }
 if (isset($spec['not null'])) {
 if ($spec['not null']) {
 $sql .= ' NOT NULL';
 }
 else {
 $sql .= ' NULL';
 }
 }
 if (isset($spec['default'])) {
 $default = is_string ($spec['default']) ? "'" . $spec['default'] . "'" : $spec['default'];
 $sql .= " default {$default}";
 }
 return $sql;
 }
 
 /**
 * Set database-engine specific properties for a field.
 *
 * @param $field
 * A field description array, as specified in the schema documentation.
 */
 protected function processField($field) {
 if (!isset($field['size'])) {
 $field['size'] = 'normal';
 }
 // Set the correct database-engine specific datatype.
 // In case one is already provided, force it to lowercase.
 if (isset($field['pgsql_type'])) {
 $field['pgsql_type'] = drupal_strtolower ($field['pgsql_type']);
 }
 else {
 $map = $this->getFieldTypeMap();
 $field['pgsql_type'] = $map[$field['type'] . ':' . $field['size']];
 }
 if (!empty($field['unsigned'])) {
 // Unsigned datatypes are not supported in PostgreSQL 8.3. In MySQL,
 // they are used to ensure a positive number is inserted and it also
 // doubles the maximum integer size that can be stored in a field.
 // The PostgreSQL schema in Drupal creates a check constraint
 // to ensure that a value inserted is >= 0. To provide the extra
 // integer capacity, here, we bump up the column field size.
 if (!isset($map)) {
 $map = $this->getFieldTypeMap();
 }
 switch ($field['pgsql_type']) {
 case 'smallint':
 $field['pgsql_type'] = $map['int:medium'];
 break;
 case 'int':
 $field['pgsql_type'] = $map['int:big'];
 break;
 }
 }
 if (isset($field['type']) && $field['type'] == 'serial') {
 unset($field['not null']);
 }
 return $field;
 }
 
 /**
 * This maps a generic data type in combination with its data size
 * to the engine-specific data type.
 */
 function getFieldTypeMap() {
 // Put :normal last so it gets preserved by array_flip. This makes
 // it much easier for modules (such as schema.module) to map
 // database types back into schema types.
 // $map does not use drupal_static as its value never changes.
 static $map = array(
 'varchar:normal' => 'varchar',
 'char:normal' => 'character',
 'text:tiny' => 'text',
 'text:small' => 'text',
 'text:medium' => 'text',
 'text:big' => 'text',
 'text:normal' => 'text',
 'int:tiny' => 'smallint',
 'int:small' => 'smallint',
 'int:medium' => 'int',
 'int:big' => 'bigint',
 'int:normal' => 'int',
 'float:tiny' => 'real',
 'float:small' => 'real',
 'float:medium' => 'real',
 'float:big' => 'double precision',
 'float:normal' => 'real',
 'numeric:normal' => 'numeric',
 'blob:big' => 'bytea',
 'blob:normal' => 'bytea',
 'serial:tiny' => 'serial',
 'serial:small' => 'serial',
 'serial:medium' => 'serial',
 'serial:big' => 'bigserial',
 'serial:normal' => 'serial',
 );
 return $map;
 }
 protected function _createKeySql($fields) {
 $return = array();
 foreach ($fields as $field) {
 if (is_array ($field)) {
 $return[] = 'substr(' . $field[0] . ', 1, ' . $field[1] . ')';
 }
 else {
 $return[] = '"' . $field . '"';
 }
 }
 return implode (', ', $return);
 }
 
 /**
 * {@inheritdoc}
 */
 public function tableExists($table) {
 // In PostgreSQL "unquoted names are always folded to lower case."
 // @see DatabaseSchema_pgsql::buildTableNameCondition().
 $prefixInfo = $this->getPrefixInfo(strtolower ($table), TRUE);
 return (bool) $this->connection
 ->query ("SELECT 1 FROM pg_tables WHERE schemaname = :schema AND tablename = :table", array(
 ':schema' => $prefixInfo['schema'],
 ':table' => $prefixInfo['table'],
 ))
 ->fetchField ();
 }
 
 /**
 * {@inheritdoc}
 */
 public function findTables($table_expression) {
 $individually_prefixed_tables = $this->connection
 ->getUnprefixedTablesMap ();
 $default_prefix = $this->connection
 ->tablePrefix ();
 $default_prefix_length = strlen ($default_prefix);
 $tables = array();
 // Load all the tables up front in order to take into account per-table
 // prefixes. The actual matching is done at the bottom of the method.
 $results = $this->connection
 ->query ("SELECT tablename FROM pg_tables WHERE schemaname = :schema", array(
 ':schema' => $this->defaultSchema,
 ));
 foreach ($results as $table) {
 // Take into account tables that have an individual prefix.
 if (isset($individually_prefixed_tables[$table->tablename])) {
 $prefix_length = strlen ($this->connection
 ->tablePrefix ($individually_prefixed_tables[$table->tablename]));
 }
 elseif ($default_prefix && substr ($table->tablename, 0, $default_prefix_length) !== $default_prefix) {
 // This table name does not start the default prefix, which means that
 // it is not managed by Drupal so it should be excluded from the result.
 continue;
 }
 else {
 $prefix_length = $default_prefix_length;
 }
 // Remove the prefix from the returned tables.
 $unprefixed_table_name = substr ($table->tablename, $prefix_length);
 // The pattern can match a table which is the same as the prefix. That
 // will become an empty string when we remove the prefix, which will
 // probably surprise the caller, besides not being a prefixed table. So
 // remove it.
 if (!empty($unprefixed_table_name)) {
 $tables[$unprefixed_table_name] = $unprefixed_table_name;
 }
 }
 // Need to use strtolower on the table name as it was used previously by
 // DatabaseSchema_pgsql::buildTableNameCondition().
 // @see https://www.drupal.org/project/drupal/issues/3262341
 $table_expression = strtolower ($table_expression);
 // Convert the table expression from its SQL LIKE syntax to a regular
 // expression and escape the delimiter that will be used for matching.
 $table_expression = str_replace (array(
 '%',
 '_',
 ), array(
 '.*?',
 '.',
 ), preg_quote ($table_expression, '/'));
 $tables = preg_grep ('/^' . $table_expression . '$/i', $tables);
 return $tables;
 }
 function renameTable($table, $new_name) {
 if (!$this->tableExists($table)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot rename @table to @table_new: table @table doesn't exist.", array(
 '@table' => $table,
 '@table_new' => $new_name,
 )));
 }
 if ($this->tableExists($new_name)) {
 throw new DatabaseSchemaObjectExistsException (t ("Cannot rename @table to @table_new: table @table_new already exists.", array(
 '@table' => $table,
 '@table_new' => $new_name,
 )));
 }
 // Get the schema and tablename for the old table.
 $old_full_name = $this->connection
 ->prefixTables ('{' . $table . '}');
 list($old_schema, $old_table_name) = strpos ($old_full_name, '.') ? explode ('.', $old_full_name) : array(
 'public',
 $old_full_name,
 );
 // Index names and constraint names are global in PostgreSQL, so we need to
 // rename them when renaming the table.
 $indexes = $this->connection
 ->query ('SELECT indexname FROM pg_indexes WHERE schemaname = :schema AND tablename = :table', array(
 ':schema' => $old_schema,
 ':table' => $old_table_name,
 ));
 foreach ($indexes as $index) {
 // Get the index type by suffix, e.g. idx/key/pkey
 $index_type = substr ($index->indexname, strrpos ($index->indexname, '_') + 1);
 // If the index is already rewritten by ensureIdentifiersLength() to not
 // exceed the 63 chars limit of PostgreSQL, we need to take care of that.
 // Example (drupal_Gk7Su_T1jcBHVuvSPeP22_I3Ni4GrVEgTYlIYnBJkro_idx).
 if (strpos ($index->indexname, 'drupal_') !== FALSE) {
 preg_match ('/^drupal_(.*)_' . preg_quote ($index_type) . '/', $index->indexname, $matches);
 $index_name = $matches[1];
 }
 else {
 if ($index_type == 'pkey') {
 // Primary keys do not have a specific name in D7.
 $index_name = '';
 }
 else {
 // Make sure to remove the suffix from index names, because
 // ensureIdentifiersLength() will add the suffix again and thus
 // would result in a wrong index name.
 preg_match ('/^' . preg_quote ($old_full_name) . '_(.*)_' . preg_quote ($index_type) . '/', $index->indexname, $matches);
 $index_name = $matches[1];
 }
 }
 $this->connection
 ->query ('ALTER INDEX ' . $index->indexname . ' RENAME TO ' . $this->ensureIdentifiersLength($new_name, $index_name, $index_type));
 }
 // Now rename the table.
 // Ensure the new table name does not include schema syntax.
 $prefixInfo = $this->getPrefixInfo($new_name);
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} RENAME TO ' . $prefixInfo['table']);
 }
 public function dropTable($table) {
 if (!$this->tableExists($table)) {
 return FALSE;
 }
 $this->connection
 ->query ('DROP TABLE {' . $table . '}');
 return TRUE;
 }
 public function addField($table, $field, $spec, $new_keys = array()) {
 if (!$this->tableExists($table)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot add field @table.@field: table doesn't exist.", array(
 '@field' => $field,
 '@table' => $table,
 )));
 }
 if ($this->fieldExists($table, $field)) {
 throw new DatabaseSchemaObjectExistsException (t ("Cannot add field @table.@field: field already exists.", array(
 '@field' => $field,
 '@table' => $table,
 )));
 }
 $fixnull = FALSE;
 if (!empty($spec['not null']) && !isset($spec['default'])) {
 $fixnull = TRUE;
 $spec['not null'] = FALSE;
 }
 $query = 'ALTER TABLE {' . $table . '} ADD COLUMN ';
 $query .= $this->createFieldSql($field, $this->processField($spec));
 $this->connection
 ->query ($query);
 if (isset($spec['initial'])) {
 $this->connection
 ->update ($table)
 ->fields (array(
 $field => $spec['initial'],
 ))
 ->execute ();
 }
 if ($fixnull) {
 $this->connection
 ->query ("ALTER TABLE {" . $table . "} ALTER {$field} SET NOT NULL");
 }
 if (isset($new_keys)) {
 $this->_createKeys($table, $new_keys);
 }
 // Add column comment.
 if (!empty($spec['description'])) {
 $this->connection
 ->query ('COMMENT ON COLUMN {' . $table . '}.' . $field . ' IS ' . $this->prepareComment($spec['description']));
 }
 }
 public function dropField($table, $field) {
 if (!$this->fieldExists($table, $field)) {
 return FALSE;
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} DROP COLUMN "' . $field . '"');
 return TRUE;
 }
 public function fieldSetDefault($table, $field, $default) {
 if (!$this->fieldExists($table, $field)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot set default value of field @table.@field: field doesn't exist.", array(
 '@table' => $table,
 '@field' => $field,
 )));
 }
 if (!isset($default)) {
 $default = 'NULL';
 }
 else {
 $default = is_string ($default) ? "'{$default}'" : $default;
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ALTER COLUMN "' . $field . '" SET DEFAULT ' . $default);
 }
 public function fieldSetNoDefault($table, $field) {
 if (!$this->fieldExists($table, $field)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot remove default value of field @table.@field: field doesn't exist.", array(
 '@table' => $table,
 '@field' => $field,
 )));
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ALTER COLUMN "' . $field . '" DROP DEFAULT');
 }
 
 /**
 * {@inheritdoc}
 */
 public function fieldExists($table, $column) {
 // In PostgreSQL "unquoted names are always folded to lower case."
 // @see DatabaseSchema_pgsql::buildTableNameCondition().
 $prefixInfo = $this->getPrefixInfo(strtolower ($table));
 return (bool) $this->connection
 ->query ("SELECT 1 FROM pg_attribute WHERE attrelid = :key::regclass AND attname = :column AND NOT attisdropped AND attnum > 0", array(
 ':key' => $prefixInfo['schema'] . '.' . $prefixInfo['table'],
 ':column' => $column,
 ))
 ->fetchField ();
 }
 public function indexExists($table, $name) {
 // Details https://www.postgresql.org/docs/10/view-pg-indexes.html
 $index_name = $this->ensureIdentifiersLength($table, $name, 'idx');
 return (bool) $this->connection
 ->query ("SELECT 1 FROM pg_indexes WHERE indexname = '{$index_name}'")
 ->fetchField ();
 }
 
 /**
 * Helper function: check if a constraint (PK, FK, UK) exists.
 *
 * @param $table
 * The name of the table.
 * @param $name
 * The name of the constraint (typically 'pkey' or '[constraint]_key').
 */
 protected function constraintExists($table, $name) {
 // ensureIdentifiersLength() expects three parameters, thus we split our
 // constraint name in a proper name and a suffix.
 if ($name == 'pkey') {
 $suffix = $name;
 $name = '';
 }
 else {
 $pos = strrpos ($name, '_');
 $suffix = substr ($name, $pos + 1);
 $name = substr ($name, 0, $pos);
 }
 $constraint_name = $this->ensureIdentifiersLength($table, $name, $suffix);
 return (bool) $this->connection
 ->query ("SELECT 1 FROM pg_constraint WHERE conname = '{$constraint_name}'")
 ->fetchField ();
 }
 public function addPrimaryKey($table, $fields) {
 if (!$this->tableExists($table)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot add primary key to table @table: table doesn't exist.", array(
 '@table' => $table,
 )));
 }
 if ($this->constraintExists($table, 'pkey')) {
 throw new DatabaseSchemaObjectExistsException (t ("Cannot add primary key to table @table: primary key already exists.", array(
 '@table' => $table,
 )));
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ADD CONSTRAINT ' . $this->ensureIdentifiersLength($table, '', 'pkey') . ' PRIMARY KEY (' . implode (',', $fields) . ')');
 }
 public function dropPrimaryKey($table) {
 if (!$this->constraintExists($table, 'pkey')) {
 return FALSE;
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} DROP CONSTRAINT ' . $this->ensureIdentifiersLength($table, '', 'pkey'));
 return TRUE;
 }
 function addUniqueKey($table, $name, $fields) {
 if (!$this->tableExists($table)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot add unique key @name to table @table: table doesn't exist.", array(
 '@table' => $table,
 '@name' => $name,
 )));
 }
 if ($this->constraintExists($table, $name . '_key')) {
 throw new DatabaseSchemaObjectExistsException (t ("Cannot add unique key @name to table @table: unique key already exists.", array(
 '@table' => $table,
 '@name' => $name,
 )));
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ADD CONSTRAINT "' . $this->ensureIdentifiersLength($table, $name, 'key') . '" UNIQUE (' . implode (',', $fields) . ')');
 }
 public function dropUniqueKey($table, $name) {
 if (!$this->constraintExists($table, $name . '_key')) {
 return FALSE;
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} DROP CONSTRAINT "' . $this->ensureIdentifiersLength($table, $name, 'key') . '"');
 return TRUE;
 }
 public function addIndex($table, $name, $fields) {
 if (!$this->tableExists($table)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot add index @name to table @table: table doesn't exist.", array(
 '@table' => $table,
 '@name' => $name,
 )));
 }
 if ($this->indexExists($table, $name)) {
 throw new DatabaseSchemaObjectExistsException (t ("Cannot add index @name to table @table: index already exists.", array(
 '@table' => $table,
 '@name' => $name,
 )));
 }
 $this->connection
 ->query ($this->_createIndexSql($table, $name, $fields));
 }
 public function dropIndex($table, $name) {
 if (!$this->indexExists($table, $name)) {
 return FALSE;
 }
 $this->connection
 ->query ('DROP INDEX ' . $this->ensureIdentifiersLength($table, $name, 'idx'));
 return TRUE;
 }
 public function changeField($table, $field, $field_new, $spec, $new_keys = array()) {
 if (!$this->fieldExists($table, $field)) {
 throw new DatabaseSchemaObjectDoesNotExistException (t ("Cannot change the definition of field @table.@name: field doesn't exist.", array(
 '@table' => $table,
 '@name' => $field,
 )));
 }
 if ($field != $field_new && $this->fieldExists($table, $field_new)) {
 throw new DatabaseSchemaObjectExistsException (t ("Cannot rename field @table.@name to @name_new: target field already exists.", array(
 '@table' => $table,
 '@name' => $field,
 '@name_new' => $field_new,
 )));
 }
 $spec = $this->processField($spec);
 // We need to typecast the new column to best be able to transfer the data
 // Schema_pgsql::getFieldTypeMap() will return possibilities that are not
 // 'cast-able' such as 'serial' - so they need to be casted int instead.
 if (in_array ($spec['pgsql_type'], array(
 'serial',
 'bigserial',
 'numeric',
 ))) {
 $typecast = 'int';
 }
 else {
 $typecast = $spec['pgsql_type'];
 }
 if (in_array ($spec['pgsql_type'], array(
 'varchar',
 'character',
 'text',
 )) && isset($spec['length'])) {
 $typecast .= '(' . $spec['length'] . ')';
 }
 elseif (isset($spec['precision']) && isset($spec['scale'])) {
 $typecast .= '(' . $spec['precision'] . ', ' . $spec['scale'] . ')';
 }
 // Remove old check constraints.
 $field_info = $this->queryFieldInformation($table, $field);
 foreach ($field_info as $check) {
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} DROP CONSTRAINT "' . $check . '"');
 }
 // Remove old default.
 $this->fieldSetNoDefault($table, $field);
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ALTER "' . $field . '" TYPE ' . $typecast . ' USING "' . $field . '"::' . $typecast);
 if (isset($spec['not null'])) {
 if ($spec['not null']) {
 $nullaction = 'SET NOT NULL';
 }
 else {
 $nullaction = 'DROP NOT NULL';
 }
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ALTER "' . $field . '" ' . $nullaction);
 }
 if (in_array ($spec['pgsql_type'], array(
 'serial',
 'bigserial',
 ))) {
 // Type "serial" is known to PostgreSQL, but *only* during table creation,
 // not when altering. Because of that, the sequence needs to be created
 // and initialized by hand.
 $seq = "{" . $table . "}_" . $field_new . "_seq";
 $this->connection
 ->query ("CREATE SEQUENCE " . $seq);
 // Set sequence to maximal field value to not conflict with existing
 // entries.
 $this->connection
 ->query ("SELECT setval('" . $seq . "', MAX(\"" . $field . '")) FROM {' . $table . "}");
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ALTER "' . $field . '" SET DEFAULT nextval(\'' . $seq . '\')');
 }
 // Rename the column if necessary.
 if ($field != $field_new) {
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} RENAME "' . $field . '" TO "' . $field_new . '"');
 }
 // Add unsigned check if necessary.
 if (!empty($spec['unsigned'])) {
 $this->connection
 ->query ('ALTER TABLE {' . $table . '} ADD CHECK ("' . $field_new . '" >= 0)');
 }
 // Add default if necessary.
 if (isset($spec['default'])) {
 $this->fieldSetDefault($table, $field_new, $spec['default']);
 }
 // Change description if necessary.
 if (!empty($spec['description'])) {
 $this->connection
 ->query ('COMMENT ON COLUMN {' . $table . '}."' . $field_new . '" IS ' . $this->prepareComment($spec['description']));
 }
 if (isset($new_keys)) {
 $this->_createKeys($table, $new_keys);
 }
 }
 protected function _createIndexSql($table, $name, $fields) {
 $query = 'CREATE INDEX "' . $this->ensureIdentifiersLength($table, $name, 'idx') . '" ON {' . $table . '} (';
 $query .= $this->_createKeySql($fields) . ')';
 return $query;
 }
 protected function _createKeys($table, $new_keys) {
 if (isset($new_keys['primary key'])) {
 $this->addPrimaryKey($table, $new_keys['primary key']);
 }
 if (isset($new_keys['unique keys'])) {
 foreach ($new_keys['unique keys'] as $name => $fields) {
 $this->addUniqueKey($table, $name, $fields);
 }
 }
 if (isset($new_keys['indexes'])) {
 foreach ($new_keys['indexes'] as $name => $fields) {
 $this->addIndex($table, $name, $fields);
 }
 }
 }
 
 /**
 * Retrieve a table or column comment.
 */
 public function getComment($table, $column = NULL) {
 $info = $this->getPrefixInfo($table);
 // Don't use {} around pg_class, pg_attribute tables.
 if (isset($column)) {
 return $this->connection
 ->query ('SELECT col_description(oid, attnum) FROM pg_class, pg_attribute WHERE attrelid = oid AND relname = ? AND attname = ?', array(
 $info['table'],
 $column,
 ))
 ->fetchField ();
 }
 else {
 return $this->connection
 ->query ('SELECT obj_description(oid, ?) FROM pg_class WHERE relname = ?', array(
 'pg_class',
 $info['table'],
 ))
 ->fetchField ();
 }
 }
 
 /**
 * Calculates a base-64 encoded, PostgreSQL-safe sha-256 hash per PostgreSQL
 * documentation: 4.1. Lexical Structure.
 *
 * @param $data
 * String to be hashed.
 *
 * @return string
 * A base-64 encoded sha-256 hash, with + and / replaced with _ and any =
 * padding characters removed.
 */
 protected function hashBase64($data) {
 // Ensure lowercase as D7's pgsql driver does not quote identifiers
 // consistently, and they are therefore folded to lowercase by PostgreSQL.
 $hash = strtolower (base64_encode (hash ('sha256', $data, TRUE)));
 // Modify the hash so it's safe to use in PostgreSQL identifiers.
 return strtr ($hash, array(
 '+' => '_',
 '/' => '_',
 '=' => '',
 ));
 }
 
 /**
 * Build a condition to match a table name against a standard information_schema.
 *
 * In PostgreSQL "unquoted names are always folded to lower case." The pgsql
 * driver does not quote table names, so they are therefore always lowercase.
 *
 * @see https://www.postgresql.org/docs/14/sql-syntax-lexical.html
 */
 protected function buildTableNameCondition($table_name, $operator = '=', $add_prefix = TRUE) {
 return parent::buildTableNameCondition(strtolower ($table_name), $operator, $add_prefix);
 }
}