original_string: public function stmt_fragment($part, $args=[]) {
  		$type = $this->dbtype;
  		if ($part == 'engine') {
  			if ($type == 'mysql')
  				# we only intent to support FOREIGN KEY-capable engines
  				return "ENGINE=InnoDB";
  			return '';
  		}
  		if ($part == "index") {
  			if ($type == 'pgsql')
  				return 'SERIAL PRIMARY KEY';
  			if ($type == 'mysql')
  				return 'INTEGER PRIMARY KEY AUTO_INCREMENT';
  			return 'INTEGER PRIMARY KEY AUTOINCREMENT';
  		}
  		if ($part == 'datetime') {
  			$delta = 0;
  			if ($args && isset($args['delta']))
  				$delta = (int)$args['delta'];
  			return $this->stmt_fragment_datetime($delta);
  		}
  		return "";
  	}
code: public function stmt_fragment($part, $args=[]) {
  		$type = $this->dbtype;
  		if ($part == 'engine') {
  			if ($type == 'mysql')
  				# we only intent to support FOREIGN KEY-capable engines
  				return "ENGINE=InnoDB";
  			return '';
  		}
  		if ($part == "index") {
  			if ($type == 'pgsql')
  				return 'SERIAL PRIMARY KEY';
  			if ($type == 'mysql')
  				return 'INTEGER PRIMARY KEY AUTO_INCREMENT';
  			return 'INTEGER PRIMARY KEY AUTOINCREMENT';
  		}
  		if ($part == 'datetime') {
  			$delta = 0;
  			if ($args && isset($args['delta']))
  				$delta = (int)$args['delta'];
  			return $this->stmt_fragment_datetime($delta);
  		}
  		return "";
  	}
code_tokens: public function stmt_fragment ( $ part , $ args = [ ] ) { $ type = $ this -> dbtype ; if ( $ part == 'engine' ) { if ( $ type == 'mysql' ) # we only intent to support FOREIGN KEY-capable engines return "ENGINE=InnoDB" ; return '' ; } if ( $ part == "index" ) { if ( $ type == 'pgsql' ) return 'SERIAL PRIMARY KEY' ; if ( $ type == 'mysql' ) return 'INTEGER PRIMARY KEY AUTO_INCREMENT' ; return 'INTEGER PRIMARY KEY AUTOINCREMENT' ; } if ( $ part == 'datetime' ) { $ delta = 0 ; if ( $ args && isset ( $ args [ 'delta' ] ) ) $ delta = ( int ) $ args [ 'delta' ] ; return $ this -> stmt_fragment_datetime ( $ delta ) ; } return "" ; }
docstring: SQL statement fragment.
  
  @param string $part A part sensitive to the database being used,
  one of these: 'engine', 'index', 'datetime'.
  @param array $args Dict of parameters for $part, for 'datetime'
  only.
docstring_tokens: SQL statement fragment .