query( sprintf( $q, $db->addQuotes( $wgDBmwschema ), $db->addQuotes( $table ), $db->addQuotes( $field ) ) ); $row = $db->fetchObject( $res ); if ( !$row ) { return null; } $n = new IBM_DB2Field; $n->type = $row->typname; $n->nullable = ( $row->attnotnull == 'N' ); $n->name = $field; $n->tablename = $table; $n->max_length = $row->attlen; return $n; } /** * Get column name * @return string column name */ function name() { return $this->name; } /** * Get table name * @return string table name */ function tableName() { return $this->tablename; } /** * Get column type * @return string column type */ function type() { return $this->type; } /** * Can column be null? * @return bool true or false */ function isNullable() { return $this->nullable; } /** * How much can you fit in the column per row? * @return int length */ function maxLength() { return $this->max_length; } } /** * Wrapper around binary large objects * @ingroup Database */ class IBM_DB2Blob { private $mData; public function __construct( $data ) { $this->mData = $data; } public function getData() { return $this->mData; } public function __toString() { return $this->mData; } } /** * Primary database interface * @ingroup Database */ class DatabaseIbm_db2 extends DatabaseBase { /* * Inherited members protected $mLastQuery = ''; protected $mPHPError = false; protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname; protected $mOut, $mOpened = false; protected $mTablePrefix; protected $mFlags; protected $mTrxLevel = 0; protected $mErrorCount = 0; protected $mLBInfo = array(); protected $mFakeSlaveLag = null, $mFakeMaster = false; * */ /** Database server port */ protected $mPort = null; /** Schema for tables, stored procedures, triggers */ protected $mSchema = null; /** Whether the schema has been applied in this session */ protected $mSchemaSet = false; /** Result of last query */ protected $mLastResult = null; /** Number of rows affected by last INSERT/UPDATE/DELETE */ protected $mAffectedRows = null; /** Number of rows returned by last SELECT */ protected $mNumRows = null; /** Connection config options - see constructor */ public $mConnOptions = array(); /** Statement config options -- see constructor */ public $mStmtOptions = array(); /** Default schema */ const USE_GLOBAL = 'mediawiki'; /** Option that applies to nothing */ const NONE_OPTION = 0x00; /** Option that applies to connection objects */ const CONN_OPTION = 0x01; /** Option that applies to statement objects */ const STMT_OPTION = 0x02; /** Regular operation mode -- minimal debug messages */ const REGULAR_MODE = 'regular'; /** Installation mode -- lots of debug messages */ const INSTALL_MODE = 'install'; /** Controls the level of debug message output */ protected $mMode = self::REGULAR_MODE; /** Last sequence value used for a primary key */ protected $mInsertId = null; ###################################### # Getters and Setters ###################################### /** * Returns true if this database supports (and uses) cascading deletes */ function cascadingDeletes() { return true; } /** * Returns true if this database supports (and uses) triggers (e.g. on the * page table) */ function cleanupTriggers() { return true; } /** * Returns true if this database is strict about what can be put into an * IP field. * Specifically, it uses a NULL value instead of an empty string. */ function strictIPs() { return true; } /** * Returns true if this database uses timestamps rather than integers */ function realTimestamps() { return true; } /** * Returns true if this database does an implicit sort when doing GROUP BY */ function implicitGroupby() { return false; } /** * Returns true if this database does an implicit order by when the column * has an index * For example: SELECT page_title FROM page LIMIT 1 */ function implicitOrderby() { return false; } /** * Returns true if this database can do a native search on IP columns * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32'; */ function searchableIPs() { return true; } /** * Returns true if this database can use functional indexes */ function functionalIndexes() { return true; } /** * Returns a unique string representing the wiki on the server */ function getWikiID() { if( $this->mSchema ) { return "{$this->mDBname}-{$this->mSchema}"; } else { return $this->mDBname; } } function getType() { return 'ibm_db2'; } /** * * @param $server String: hostname of database server * @param $user String: username * @param $password String: password * @param $dbName String: database name on the server * @param $flags Integer: database behaviour flags (optional, unused) * @param $schema String */ public function __construct( $server = false, $user = false, $password = false, $dbName = false, $flags = 0, $schema = self::USE_GLOBAL ) { global $wgDBmwschema; if ( $schema == self::USE_GLOBAL ) { $this->mSchema = $wgDBmwschema; } else { $this->mSchema = $schema; } // configure the connection and statement objects $this->setDB2Option( 'db2_attr_case', 'DB2_CASE_LOWER', self::CONN_OPTION | self::STMT_OPTION ); $this->setDB2Option( 'deferred_prepare', 'DB2_DEFERRED_PREPARE_ON', self::STMT_OPTION ); $this->setDB2Option( 'rowcount', 'DB2_ROWCOUNT_PREFETCH_ON', self::STMT_OPTION ); parent::__construct( $server, $user, $password, $dbName, DBO_TRX | $flags ); } /** * Enables options only if the ibm_db2 extension version supports them * @param $name String: name of the option in the options array * @param $const String: name of the constant holding the right option value * @param $type Integer: whether this is a Connection or Statement otion */ private function setDB2Option( $name, $const, $type ) { if ( defined( $const ) ) { if ( $type & self::CONN_OPTION ) { $this->mConnOptions[$name] = constant( $const ); } if ( $type & self::STMT_OPTION ) { $this->mStmtOptions[$name] = constant( $const ); } } else { $this->installPrint( "$const is not defined. ibm_db2 version is likely too low." ); } } /** * Outputs debug information in the appropriate place * @param $string String: the relevant debug message */ private function installPrint( $string ) { wfDebug( "$string\n" ); if ( $this->mMode == self::INSTALL_MODE ) { print "
  • $string
  • "; flush(); } } /** * Opens a database connection and returns it * Closes any existing connection * * @param $server String: hostname * @param $user String * @param $password String * @param $dbName String: database name * @return a fresh connection */ public function open( $server, $user, $password, $dbName ) { // Load the port number global $wgDBport; wfProfileIn( __METHOD__ ); // Load IBM DB2 driver if missing wfDl( 'ibm_db2' ); // Test for IBM DB2 support, to avoid suppressed fatal error if ( !function_exists( 'db2_connect' ) ) { $error = <<installPrint( $error ); $this->reportConnectionError( $error ); } if ( strlen( $user ) < 1 ) { wfProfileOut( __METHOD__ ); return null; } // Close existing connection $this->close(); // Cache conn info $this->mServer = $server; $this->mPort = $port = $wgDBport; $this->mUser = $user; $this->mPassword = $password; $this->mDBname = $dbName; $this->openUncataloged( $dbName, $user, $password, $server, $port ); // Apply connection config db2_set_option( $this->mConn, $this->mConnOptions, 1 ); // Some MediaWiki code is still transaction-less (?). // The strategy is to keep AutoCommit on for that code // but switch it off whenever a transaction is begun. db2_autocommit( $this->mConn, DB2_AUTOCOMMIT_ON ); if ( !$this->mConn ) { $this->installPrint( "DB connection error\n" ); $this->installPrint( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" ); $this->installPrint( $this->lastError() . "\n" ); wfProfileOut( __METHOD__ ); return null; } $this->mOpened = true; $this->applySchema(); wfProfileOut( __METHOD__ ); return $this->mConn; } /** * Opens a cataloged database connection, sets mConn */ protected function openCataloged( $dbName, $user, $password ) { @$this->mConn = db2_pconnect( $dbName, $user, $password ); } /** * Opens an uncataloged database connection, sets mConn */ protected function openUncataloged( $dbName, $user, $password, $server, $port ) { $str = "DRIVER={IBM DB2 ODBC DRIVER};"; $str .= "DATABASE=$dbName;"; $str .= "HOSTNAME=$server;"; // port was formerly validated to not be 0 $str .= "PORT=$port;"; $str .= "PROTOCOL=TCPIP;"; $str .= "UID=$user;"; $str .= "PWD=$password;"; @$this->mConn = db2_pconnect( $str, $user, $password ); } /** * Closes a database connection, if it is open * Returns success, true if already closed */ public function close() { $this->mOpened = false; if ( $this->mConn ) { if ( $this->trxLevel() > 0 ) { $this->commit(); } return db2_close( $this->mConn ); } else { return true; } } /** * Returns a fresh instance of this class * * @param $server String: hostname of database server * @param $user String: username * @param $password String * @param $dbName String: database name on the server * @param $flags Integer: database behaviour flags (optional, unused) * @return DatabaseIbm_db2 object */ static function newFromParams( $server, $user, $password, $dbName, $flags = 0 ) { return new DatabaseIbm_db2( $server, $user, $password, $dbName, $flags ); } /** * Retrieves the most current database error * Forces a database rollback */ public function lastError() { $connerr = db2_conn_errormsg(); if ( $connerr ) { //$this->rollback(); return $connerr; } $stmterr = db2_stmt_errormsg(); if ( $stmterr ) { //$this->rollback(); return $stmterr; } return false; } /** * Get the last error number * Return 0 if no error * @return integer */ public function lastErrno() { $connerr = db2_conn_error(); if ( $connerr ) { return $connerr; } $stmterr = db2_stmt_error(); if ( $stmterr ) { return $stmterr; } return 0; } /** * Is a database connection open? * @return */ public function isOpen() { return $this->mOpened; } /** * The DBMS-dependent part of query() * @param $sql String: SQL query. * @return object Result object for fetch functions or false on failure * @access private */ /*private*/ public function doQuery( $sql ) { $this->applySchema(); $ret = db2_exec( $this->mConn, $sql, $this->mStmtOptions ); if( $ret == false ) { $error = db2_stmt_errormsg(); $this->installPrint( "
    $sql
    " ); $this->installPrint( $error ); throw new DBUnexpectedError( $this, 'SQL error: ' . htmlspecialchars( $error ) ); } $this->mLastResult = $ret; $this->mAffectedRows = null; // Not calculated until asked for return $ret; } /** * @return string Version information from the database */ public function getServerVersion() { $info = db2_server_info( $this->mConn ); return $info->DBMS_VER; } /** * Queries whether a given table exists * @return boolean */ public function tableExists( $table ) { $schema = $this->mSchema; $sql = <<< EOF SELECT COUNT( * ) FROM SYSIBM.SYSTABLES ST WHERE ST.NAME = '$table' AND ST.CREATOR = '$schema' EOF; $res = $this->query( $sql ); if ( !$res ) { return false; } // If the table exists, there should be one of it @$row = $this->fetchRow( $res ); $count = $row[0]; if ( $count == '1' || $count == 1 ) { return true; } return false; } /** * Fetch the next row from the given result object, in object form. * Fields can be retrieved with $row->fieldname, with fields acting like * member variables. * * @param $res SQL result object as returned from Database::query(), etc. * @return DB2 row object * @throws DBUnexpectedError Thrown if the database returns an error */ public function fetchObject( $res ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } @$row = db2_fetch_object( $res ); if( $this->lastErrno() ) { throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) ); } return $row; } /** * Fetch the next row from the given result object, in associative array * form. Fields are retrieved with $row['fieldname']. * * @param $res SQL result object as returned from Database::query(), etc. * @return DB2 row object * @throws DBUnexpectedError Thrown if the database returns an error */ public function fetchRow( $res ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } @$row = db2_fetch_array( $res ); if ( $this->lastErrno() ) { throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) ); } return $row; } /** * Create tables, stored procedures, and so on */ public function setup_database() { try { // TODO: switch to root login if available // Switch into the correct namespace $this->applySchema(); $this->begin(); $res = $this->sourceFile( "../maintenance/ibm_db2/tables.sql" ); if ( $res !== true ) { print ' FAILED: ' . htmlspecialchars( $res ) . ''; } else { print ' done'; } $res = $this->sourceFile( "../maintenance/ibm_db2/foreignkeys.sql" ); if ( $res !== true ) { print ' FAILED: ' . htmlspecialchars( $res ) . ''; } else { print '
  • Foreign keys done
  • '; } // TODO: populate interwiki links if ( $this->lastError() ) { $this->installPrint( 'Errors encountered during table creation -- rolled back' ); $this->installPrint( 'Please install again' ); $this->rollback(); } else { $this->commit(); } } catch ( MWException $mwe ) { print "
    $mwe

    "; } } /** * Escapes strings * Doesn't escape numbers * * @param $s String: string to escape * @return escaped string */ public function addQuotes( $s ) { //$this->installPrint( "DB2::addQuotes( $s )\n" ); if ( is_null( $s ) ) { return 'NULL'; } elseif ( $s instanceof Blob ) { return "'" . $s->fetch( $s ) . "'"; } elseif ( $s instanceof IBM_DB2Blob ) { return "'" . $this->decodeBlob( $s ) . "'"; } $s = $this->strencode( $s ); if ( is_numeric( $s ) ) { return $s; } else { return "'$s'"; } } /** * Verifies that a DB2 column/field type is numeric * * @param $type String: DB2 column type * @return Boolean: true if numeric */ public function is_numeric_type( $type ) { switch ( strtoupper( $type ) ) { case 'SMALLINT': case 'INTEGER': case 'INT': case 'BIGINT': case 'DECIMAL': case 'REAL': case 'DOUBLE': case 'DECFLOAT': return true; } return false; } /** * Alias for addQuotes() * @param $s String: string to escape * @return escaped string */ public function strencode( $s ) { // Bloody useless function // Prepends backslashes to \x00, \n, \r, \, ', " and \x1a. // But also necessary $s = db2_escape_string( $s ); // Wide characters are evil -- some of them look like ' $s = utf8_encode( $s ); // Fix its stupidity $from = array( "\\\\", "\\'", '\\n', '\\t', '\\"', '\\r' ); $to = array( "\\", "''", "\n", "\t", '"', "\r" ); $s = str_replace( $from, $to, $s ); // DB2 expects '', not \' escaping return $s; } /** * Switch into the database schema */ protected function applySchema() { if ( !( $this->mSchemaSet ) ) { $this->mSchemaSet = true; $this->begin(); $this->doQuery( "SET SCHEMA = $this->mSchema" ); $this->commit(); } } /** * Start a transaction (mandatory) */ public function begin( $fname = 'DatabaseIbm_db2::begin' ) { // BEGIN is implicit for DB2 // However, it requires that AutoCommit be off. // Some MediaWiki code is still transaction-less (?). // The strategy is to keep AutoCommit on for that code // but switch it off whenever a transaction is begun. db2_autocommit( $this->mConn, DB2_AUTOCOMMIT_OFF ); $this->mTrxLevel = 1; } /** * End a transaction * Must have a preceding begin() */ public function commit( $fname = 'DatabaseIbm_db2::commit' ) { db2_commit( $this->mConn ); // Some MediaWiki code is still transaction-less (?). // The strategy is to keep AutoCommit on for that code // but switch it off whenever a transaction is begun. db2_autocommit( $this->mConn, DB2_AUTOCOMMIT_ON ); $this->mTrxLevel = 0; } /** * Cancel a transaction */ public function rollback( $fname = 'DatabaseIbm_db2::rollback' ) { db2_rollback( $this->mConn ); // turn auto-commit back on // not sure if this is appropriate db2_autocommit( $this->mConn, DB2_AUTOCOMMIT_ON ); $this->mTrxLevel = 0; } /** * Makes an encoded list of strings from an array * $mode: * LIST_COMMA - comma separated, no field names * LIST_AND - ANDed WHERE clause (without the WHERE) * LIST_OR - ORed WHERE clause (without the WHERE) * LIST_SET - comma separated with field names, like a SET clause * LIST_NAMES - comma separated field names * LIST_SET_PREPARED - like LIST_SET, except with ? tokens as values */ function makeList( $a, $mode = LIST_COMMA ) { if ( !is_array( $a ) ) { throw new DBUnexpectedError( $this, 'DatabaseIbm_db2::makeList called with incorrect parameters' ); } // if this is for a prepared UPDATE statement // (this should be promoted to the parent class // once other databases use prepared statements) if ( $mode == LIST_SET_PREPARED ) { $first = true; $list = ''; foreach ( $a as $field => $value ) { if ( !$first ) { $list .= ", $field = ?"; } else { $list .= "$field = ?"; $first = false; } } $list .= ''; return $list; } // otherwise, call the usual function return parent::makeList( $a, $mode ); } /** * Construct a LIMIT query with optional offset * This is used for query pages * * @param $sql string SQL query we will append the limit too * @param $limit integer the SQL limit * @param $offset integer the SQL offset (default false) */ public function limitResult( $sql, $limit, $offset=false ) { if( !is_numeric( $limit ) ) { throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" ); } if( $offset ) { if ( stripos( $sql, 'where' ) === false ) { return "$sql AND ( ROWNUM BETWEEN $offset AND $offset+$limit )"; } else { return "$sql WHERE ( ROWNUM BETWEEN $offset AND $offset+$limit )"; } } return "$sql FETCH FIRST $limit ROWS ONLY "; } /** * Handle reserved keyword replacement in table names * * @param $name Object * @return String */ public function tableName( $name ) { // we want maximum compatibility with MySQL schema return $name; } /** * Generates a timestamp in an insertable format * * @param $ts timestamp * @return String: timestamp value */ public function timestamp( $ts = 0 ) { // TS_MW cannot be easily distinguished from an integer return wfTimestamp( TS_DB2, $ts ); } /** * Return the next in a sequence, save the value for retrieval via insertId() * @param $seqName String: name of a defined sequence in the database * @return next value in that sequence */ public function nextSequenceValue( $seqName ) { // Not using sequences in the primary schema to allow for easier migration // from MySQL // Emulating MySQL behaviour of using NULL to signal that sequences // aren't used /* $safeseq = preg_replace( "/'/", "''", $seqName ); $res = $this->query( "VALUES NEXTVAL FOR $safeseq" ); $row = $this->fetchRow( $res ); $this->mInsertId = $row[0]; return $this->mInsertId; */ return null; } /** * This must be called after nextSequenceVal * @return Last sequence value used as a primary key */ public function insertId() { return $this->mInsertId; } /** * Updates the mInsertId property with the value of the last insert * into a generated column * * @param $table String: sanitized table name * @param $primaryKey Mixed: string name of the primary key * @param $stmt Resource: prepared statement resource * of the SELECT primary_key FROM FINAL TABLE ( INSERT ... ) form */ private function calcInsertId( $table, $primaryKey, $stmt ) { if ( $primaryKey ) { $this->mInsertId = db2_last_insert_id( $this->mConn ); } } /** * INSERT wrapper, inserts an array into a table * * $args may be a single associative array, or an array of arrays * with numeric keys, for multi-row insert * * @param $table String: Name of the table to insert to. * @param $args Array: Items to insert into the table. * @param $fname String: Name of the function, for profiling * @param $options String or Array. Valid options: IGNORE * * @return bool Success of insert operation. IGNORE always returns true. */ public function insert( $table, $args, $fname = 'DatabaseIbm_db2::insert', $options = array() ) { if ( !count( $args ) ) { return true; } // get database-specific table name (not used) $table = $this->tableName( $table ); // format options as an array $options = IBM_DB2Helper::makeArray( $options ); // format args as an array of arrays if ( !( isset( $args[0] ) && is_array( $args[0] ) ) ) { $args = array( $args ); } // prevent insertion of NULL into primary key columns list( $args, $primaryKeys ) = $this->removeNullPrimaryKeys( $table, $args ); // if there's only one primary key // we'll be able to read its value after insertion $primaryKey = false; if ( count( $primaryKeys ) == 1 ) { $primaryKey = $primaryKeys[0]; } // get column names $keys = array_keys( $args[0] ); $key_count = count( $keys ); // If IGNORE is set, we use savepoints to emulate mysql's behavior $ignore = in_array( 'IGNORE', $options ) ? 'mw' : ''; // assume success $res = true; // If we are not in a transaction, we need to be for savepoint trickery if ( !$this->mTrxLevel ) { $this->begin(); } $sql = "INSERT INTO $table ( " . implode( ',', $keys ) . ' ) VALUES '; if ( $key_count == 1 ) { $sql .= '( ? )'; } else { $sql .= '( ?' . str_repeat( ',?', $key_count-1 ) . ' )'; } //$this->installPrint( "Preparing the following SQL:" ); //$this->installPrint( "$sql" ); //$this->installPrint( print_r( $args, true )); $stmt = $this->prepare( $sql ); // start a transaction/enter transaction mode $this->begin(); if ( !$ignore ) { //$first = true; foreach ( $args as $row ) { //$this->installPrint( "Inserting " . print_r( $row, true )); // insert each row into the database $res = $res & $this->execute( $stmt, $row ); if ( !$res ) { $this->installPrint( 'Last error:' ); $this->installPrint( $this->lastError() ); } // get the last inserted value into a generated column $this->calcInsertId( $table, $primaryKey, $stmt ); } } else { $olde = error_reporting( 0 ); // For future use, we may want to track the number of actual inserts // Right now, insert (all writes) simply return true/false $numrowsinserted = 0; // always return true $res = true; foreach ( $args as $row ) { $overhead = "SAVEPOINT $ignore ON ROLLBACK RETAIN CURSORS"; db2_exec( $this->mConn, $overhead, $this->mStmtOptions ); $res2 = $this->execute( $stmt, $row ); if ( !$res2 ) { $this->installPrint( 'Last error:' ); $this->installPrint( $this->lastError() ); } // get the last inserted value into a generated column $this->calcInsertId( $table, $primaryKey, $stmt ); $errNum = $this->lastErrno(); if ( $errNum ) { db2_exec( $this->mConn, "ROLLBACK TO SAVEPOINT $ignore", $this->mStmtOptions ); } else { db2_exec( $this->mConn, "RELEASE SAVEPOINT $ignore", $this->mStmtOptions ); $numrowsinserted++; } } $olde = error_reporting( $olde ); // Set the affected row count for the whole operation $this->mAffectedRows = $numrowsinserted; } // commit either way $this->commit(); $this->freePrepared( $stmt ); return $res; } /** * Given a table name and a hash of columns with values * Removes primary key columns from the hash where the value is NULL * * @param $table String: name of the table * @param $args Array of hashes of column names with values * @return Array: tuple( filtered array of columns, array of primary keys ) */ private function removeNullPrimaryKeys( $table, $args ) { $schema = $this->mSchema; // find out the primary keys $keyres = db2_primary_keys( $this->mConn, null, strtoupper( $schema ), strtoupper( $table ) ); $keys = array(); for ( $row = $this->fetchObject( $keyres ); $row != null; $row = $this->fetchObject( $keyres ) ) { $keys[] = strtolower( $row->column_name ); } // remove primary keys foreach ( $args as $ai => $row ) { foreach ( $keys as $key ) { if ( $row[$key] == null ) { unset( $row[$key] ); } } $args[$ai] = $row; } // return modified hash return array( $args, $keys ); } /** * UPDATE wrapper, takes a condition array and a SET array * * @param $table String: The table to UPDATE * @param $values An array of values to SET * @param $conds An array of conditions ( WHERE ). Use '*' to update all rows. * @param $fname String: The Class::Function calling this function * ( for the log ) * @param $options An array of UPDATE options, can be one or * more of IGNORE, LOW_PRIORITY * @return Boolean */ public function update( $table, $values, $conds, $fname = 'DatabaseIbm_db2::update', $options = array() ) { $table = $this->tableName( $table ); $opts = $this->makeUpdateOptions( $options ); $sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET_PREPARED ); if ( $conds != '*' ) { $sql .= " WHERE " . $this->makeList( $conds, LIST_AND ); } $stmt = $this->prepare( $sql ); $this->installPrint( 'UPDATE: ' . print_r( $values, true ) ); // assuming for now that an array with string keys will work // if not, convert to simple array first $result = $this->execute( $stmt, $values ); $this->freePrepared( $stmt ); return $result; } /** * DELETE query wrapper * * Use $conds == "*" to delete all rows */ public function delete( $table, $conds, $fname = 'DatabaseIbm_db2::delete' ) { if ( !$conds ) { throw new DBUnexpectedError( $this, 'DatabaseIbm_db2::delete() called with no conditions' ); } $table = $this->tableName( $table ); $sql = "DELETE FROM $table"; if ( $conds != '*' ) { $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND ); } $result = $this->query( $sql, $fname ); return $result; } /** * Returns the number of rows affected by the last query or 0 * @return Integer: the number of rows affected by the last query */ public function affectedRows() { if ( !is_null( $this->mAffectedRows ) ) { // Forced result for simulated queries return $this->mAffectedRows; } if( empty( $this->mLastResult ) ) { return 0; } return db2_num_rows( $this->mLastResult ); } /** * Simulates REPLACE with a DELETE followed by INSERT * @param $table Object * @param $uniqueIndexes Array consisting of indexes and arrays of indexes * @param $rows Array: rows to insert * @param $fname String: name of the function for profiling * @return nothing */ function replace( $table, $uniqueIndexes, $rows, $fname = 'DatabaseIbm_db2::replace' ) { $table = $this->tableName( $table ); if ( count( $rows )==0 ) { return; } # Single row case if ( !is_array( reset( $rows ) ) ) { $rows = array( $rows ); } foreach( $rows as $row ) { # Delete rows which collide if ( $uniqueIndexes ) { $sql = "DELETE FROM $table WHERE "; $first = true; foreach ( $uniqueIndexes as $index ) { if ( $first ) { $first = false; $sql .= '( '; } else { $sql .= ' ) OR ( '; } if ( is_array( $index ) ) { $first2 = true; foreach ( $index as $col ) { if ( $first2 ) { $first2 = false; } else { $sql .= ' AND '; } $sql .= $col . '=' . $this->addQuotes( $row[$col] ); } } else { $sql .= $index . '=' . $this->addQuotes( $row[$index] ); } } $sql .= ' )'; $this->query( $sql, $fname ); } # Now insert the row $sql = "INSERT INTO $table ( " . $this->makeList( array_keys( $row ), LIST_NAMES ) .' ) VALUES ( ' . $this->makeList( $row, LIST_COMMA ) . ' )'; $this->query( $sql, $fname ); } } /** * Returns the number of rows in the result set * Has to be called right after the corresponding select query * @param $res Object result set * @return Integer: number of rows */ public function numRows( $res ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } if ( $this->mNumRows ) { return $this->mNumRows; } else { return 0; } } /** * Moves the row pointer of the result set * @param $res Object: result set * @param $row Integer: row number * @return success or failure */ public function dataSeek( $res, $row ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } return db2_fetch_row( $res, $row ); } ### # Fix notices in Block.php ### /** * Frees memory associated with a statement resource * @param $res Object: statement resource to free * @return Boolean success or failure */ public function freeResult( $res ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } if ( !@db2_free_result( $res ) ) { throw new DBUnexpectedError( $this, "Unable to free DB2 result\n" ); } } /** * Returns the number of columns in a resource * @param $res Object: statement resource * @return Number of fields/columns in resource */ public function numFields( $res ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } return db2_num_fields( $res ); } /** * Returns the nth column name * @param $res Object: statement resource * @param $n Integer: Index of field or column * @return String name of nth column */ public function fieldName( $res, $n ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } return db2_field_name( $res, $n ); } /** * SELECT wrapper * * @param $table Array or string, table name(s) (prefix auto-added) * @param $vars Array or string, field name(s) to be retrieved * @param $conds Array or string, condition(s) for WHERE * @param $fname String: calling function name (use __METHOD__) * for logs/profiling * @param $options Associative array of options * (e.g. array('GROUP BY' => 'page_title')), * see Database::makeSelectOptions code for list of * supported stuff * @param $join_conds Associative array of table join conditions (optional) * (e.g. array( 'page' => array('LEFT JOIN', * 'page_latest=rev_id') ) * @return Mixed: database result resource for fetch functions or false * on failure */ public function select( $table, $vars, $conds = '', $fname = 'DatabaseIbm_db2::select', $options = array(), $join_conds = array() ) { $res = parent::select( $table, $vars, $conds, $fname, $options, $join_conds ); // We must adjust for offset if ( isset( $options['LIMIT'] ) && isset ( $options['OFFSET'] ) ) { $limit = $options['LIMIT']; $offset = $options['OFFSET']; } // DB2 does not have a proper num_rows() function yet, so we must emulate // DB2 9.5.4 and the corresponding ibm_db2 driver will introduce // a working one // TODO: Yay! // we want the count $vars2 = array( 'count( * ) as num_rows' ); // respecting just the limit option $options2 = array(); if ( isset( $options['LIMIT'] ) ) { $options2['LIMIT'] = $options['LIMIT']; } // but don't try to emulate for GROUP BY if ( isset( $options['GROUP BY'] ) ) { return $res; } $res2 = parent::select( $table, $vars2, $conds, $fname, $options2, $join_conds ); $obj = $this->fetchObject( $res2 ); $this->mNumRows = $obj->num_rows; return $res; } /** * Handles ordering, grouping, and having options ('GROUP BY' => colname) * Has limited support for per-column options (colnum => 'DISTINCT') * * @private * * @param $options Associative array of options to be turned into * an SQL query, valid keys are listed in the function. * @return Array */ function makeSelectOptions( $options ) { $preLimitTail = $postLimitTail = ''; $startOpts = ''; $noKeyOptions = array(); foreach ( $options as $key => $option ) { if ( is_numeric( $key ) ) { $noKeyOptions[$option] = true; } } if ( isset( $options['GROUP BY'] ) ) { $preLimitTail .= " GROUP BY {$options['GROUP BY']}"; } if ( isset( $options['HAVING'] ) ) { $preLimitTail .= " HAVING {$options['HAVING']}"; } if ( isset( $options['ORDER BY'] ) ) { $preLimitTail .= " ORDER BY {$options['ORDER BY']}"; } if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) { $startOpts .= 'DISTINCT'; } return array( $startOpts, '', $preLimitTail, $postLimitTail ); } /** * Returns link to IBM DB2 free download * @return String: wikitext of a link to the server software's web site */ public static function getSoftwareLink() { return '[http://www.ibm.com/db2/express/ IBM DB2]'; } /** * Get search engine class. All subclasses of this * need to implement this if they wish to use searching. * * @return String */ public function getSearchEngine() { return 'SearchIBM_DB2'; } /** * Did the last database access fail because of deadlock? * @return Boolean */ public function wasDeadlock() { // get SQLSTATE $err = $this->lastErrno(); switch( $err ) { // This is literal port of the MySQL logic and may be wrong for DB2 case '40001': // sql0911n, Deadlock or timeout, rollback case '57011': // sql0904n, Resource unavailable, no rollback case '57033': // sql0913n, Deadlock or timeout, no rollback $this->installPrint( "In a deadlock because of SQLSTATE $err" ); return true; } return false; } /** * Ping the server and try to reconnect if it there is no connection * The connection may be closed and reopened while this happens * @return Boolean: whether the connection exists */ public function ping() { // db2_ping() doesn't exist // Emulate $this->close(); $this->mConn = $this->openUncataloged( $this->mDBName, $this->mUser, $this->mPassword, $this->mServer, $this->mPort ); return false; } ###################################### # Unimplemented and not applicable ###################################### /** * Not implemented * @return string '' */ public function getStatus( $which = '%' ) { $this->installPrint( 'Not implemented for DB2: getStatus()' ); return ''; } /** * Not implemented * @return string $sql */ public function limitResultForUpdate( $sql, $num ) { $this->installPrint( 'Not implemented for DB2: limitResultForUpdate()' ); return $sql; } /** * Only useful with fake prepare like in base Database class * @return string */ public function fillPreparedArg( $matches ) { $this->installPrint( 'Not useful for DB2: fillPreparedArg()' ); return ''; } ###################################### # Reflection ###################################### /** * Returns information about an index * If errors are explicitly ignored, returns NULL on failure * @param $table String: table name * @param $index String: index name * @param $fname String: function name for logging and profiling * @return Object query row in object form */ public function indexInfo( $table, $index, $fname = 'DatabaseIbm_db2::indexExists' ) { $table = $this->tableName( $table ); $sql = <<query( $sql, $fname ); if ( !$res ) { return null; } $row = $this->fetchObject( $res ); if ( $row != null ) { return $row; } else { return false; } } /** * Returns an information object on a table column * @param $table String: table name * @param $field String: column name * @return IBM_DB2Field */ public function fieldInfo( $table, $field ) { return IBM_DB2Field::fromText( $this, $table, $field ); } /** * db2_field_type() wrapper * @param $res Object: result of executed statement * @param $index Mixed: number or name of the column * @return String column type */ public function fieldType( $res, $index ) { if ( $res instanceof ResultWrapper ) { $res = $res->result; } return db2_field_type( $res, $index ); } /** * Verifies that an index was created as unique * @param $table String: table name * @param $index String: index name * @param $fname function name for profiling * @return Bool */ public function indexUnique ( $table, $index, $fname = 'DatabaseIbm_db2::indexUnique' ) { $table = $this->tableName( $table ); $sql = <<query( $sql, $fname ); if ( !$res ) { return null; } if ( $this->fetchObject( $res ) ) { return true; } return false; } /** * Returns the size of a text field, or -1 for "unlimited" * @param $table String: table name * @param $field String: column name * @return Integer: length or -1 for unlimited */ public function textFieldSize( $table, $field ) { $table = $this->tableName( $table ); $sql = <<query( $sql ); $row = $this->fetchObject( $res ); $size = $row->size; return $size; } /** * DELETE where the condition is a join * @param $delTable String: deleting from this table * @param $joinTable String: using data from this table * @param $delVar String: variable in deleteable table * @param $joinVar String: variable in data table * @param $conds Array: conditionals for join table * @param $fname String: function name for profiling */ public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = "DatabaseIbm_db2::deleteJoin" ) { if ( !$conds ) { throw new DBUnexpectedError( $this, 'DatabaseIbm_db2::deleteJoin() called with empty $conds' ); } $delTable = $this->tableName( $delTable ); $joinTable = $this->tableName( $joinTable ); $sql = <<makeList( $conds, LIST_AND ); } $sql .= ' )'; $this->query( $sql, $fname ); } /** * Description is left as an exercise for the reader * @param $b Mixed: data to be encoded * @return IBM_DB2Blob */ public function encodeBlob( $b ) { return new IBM_DB2Blob( $b ); } /** * Description is left as an exercise for the reader * @param $b IBM_DB2Blob: data to be decoded * @return mixed */ public function decodeBlob( $b ) { return "$b"; } /** * Convert into a list of string being concatenated * @param $stringList Array: strings that need to be joined together * by the SQL engine * @return String: joined by the concatenation operator */ public function buildConcat( $stringList ) { // || is equivalent to CONCAT // Sample query: VALUES 'foo' CONCAT 'bar' CONCAT 'baz' return implode( ' || ', $stringList ); } /** * Generates the SQL required to convert a DB2 timestamp into a Unix epoch * @param $column String: name of timestamp column * @return String: SQL code */ public function extractUnixEpoch( $column ) { // TODO // see SpecialAncientpages } ###################################### # Prepared statements ###################################### /** * Intended to be compatible with the PEAR::DB wrapper functions. * http://pear.php.net/manual/en/package.database.db.intro-execute.php * * ? = scalar value, quoted as necessary * ! = raw SQL bit (a function for instance) * & = filename; reads the file and inserts as a blob * (we don't use this though...) * @param $sql String: SQL statement with appropriate markers * @param $func String: Name of the function, for profiling * @return resource a prepared DB2 SQL statement */ public function prepare( $sql, $func = 'DB2::prepare' ) { $stmt = db2_prepare( $this->mConn, $sql, $this->mStmtOptions ); return $stmt; } /** * Frees resources associated with a prepared statement * @return Boolean success or failure */ public function freePrepared( $prepared ) { return db2_free_stmt( $prepared ); } /** * Execute a prepared query with the various arguments * @param $prepared String: the prepared sql * @param $args Mixed: either an array here, or put scalars as varargs * @return Resource: results object */ public function execute( $prepared, $args = null ) { if( !is_array( $args ) ) { # Pull the var args $args = func_get_args(); array_shift( $args ); } $res = db2_execute( $prepared, $args ); if ( !$res ) { $this->installPrint( db2_stmt_errormsg() ); } return $res; } /** * Prepare & execute an SQL statement, quoting and inserting arguments * in the appropriate places. * @param $query String * @param $args ... */ public function safeQuery( $query, $args = null ) { // copied verbatim from Database.php $prepared = $this->prepare( $query, 'DB2::safeQuery' ); if( !is_array( $args ) ) { # Pull the var args $args = func_get_args(); array_shift( $args ); } $retval = $this->execute( $prepared, $args ); $this->freePrepared( $prepared ); return $retval; } /** * For faking prepared SQL statements on DBs that don't support * it directly. * @param $preparedQuery String: a 'preparable' SQL statement * @param $args Array of arguments to fill it with * @return String: executable statement */ public function fillPrepared( $preparedQuery, $args ) { reset( $args ); $this->preparedArgs =& $args; foreach ( $args as $i => $arg ) { db2_bind_param( $preparedQuery, $i+1, $args[$i] ); } return $preparedQuery; } /** * Switches module between regular and install modes */ public function setMode( $mode ) { $old = $this->mMode; $this->mMode = $mode; return $old; } /** * Bitwise negation of a column or value in SQL * Same as (~field) in C * @param $field String * @return String */ function bitNot( $field ) { // expecting bit-fields smaller than 4bytes return "BITNOT( $field )"; } /** * Bitwise AND of two columns or values in SQL * Same as (fieldLeft & fieldRight) in C * @param $fieldLeft String * @param $fieldRight String * @return String */ function bitAnd( $fieldLeft, $fieldRight ) { return "BITAND( $fieldLeft, $fieldRight )"; } /** * Bitwise OR of two columns or values in SQL * Same as (fieldLeft | fieldRight) in C * @param $fieldLeft String * @param $fieldRight String * @return String */ function bitOr( $fieldLeft, $fieldRight ) { return "BITOR( $fieldLeft, $fieldRight )"; } } class IBM_DB2Helper { public static function makeArray( $maybeArray ) { if ( !is_array( $maybeArray ) ) { return array( $maybeArray ); } return $maybeArray; } }