adodb-datadict.inc.php

<?php

/**
  V5.04a 25 Mar 2008   (c) 2000-2008 John Lim (jlim#natsoft.com.my). All rights reserved.
  Released under both BSD license and Lesser GPL library license. 
  Whenever there is any discrepancy between the two licenses, 
  the BSD license will take precedence.
	
  Set tabs to 4 for best viewing.
 
 	DOCUMENTATION:
	
		See adodb/tests/test-datadict.php for docs and examples.
*/

/*
	Test script for parser
*/

// security - hide paths
if (!defined('ADODB_DIR')) die();

function Lens_ParseTest()
{
$str = "`zcol ACOL` NUMBER(32,2) DEFAULT 'The \"cow\" (and Jim''s dog) jumps over the moon' PRIMARY, INTI INT AUTO DEFAULT 0, zcol2\"afs ds";
print "<p>$str</p>";
$a= Lens_ParseArgs($str);
print "<pre>";
print_r($a);
print "</pre>";
}


if (!function_exists('ctype_alnum')) {
	function ctype_alnum($text) {
		return preg_match('/^[a-z0-9]*$/i', $text);
	}
}

//Lens_ParseTest();

/**
	Parse arguments, treat "text" (text) and 'text' as quotation marks.
	To escape, use "" or '' or ))
	
	Will read in "abc def" sans quotes, as: abc def
	Same with 'abc def'.
	However if `abc def`, then will read in as `abc def`
	
	@param endstmtchar    Character that indicates end of statement
	@param tokenchars     Include the following characters in tokens apart from A-Z and 0-9 
	@returns 2 dimensional array containing parsed tokens.
*/
function Lens_ParseArgs($args,$endstmtchar=',',$tokenchars='_.-')
{
	$pos = 0;
	$intoken = false;
	$stmtno = 0;
	$endquote = false;
	$tokens = array();
	$tokens[$stmtno] = array();
	$max = strlen($args);
	$quoted = false;
	$tokarr = array();
	
	while ($pos < $max) {
		$ch = substr($args,$pos,1);
		switch($ch) {
		case ' ':
		case "\t":
		case "\n":
		case "\r":
			if (!$quoted) {
				if ($intoken) {
					$intoken = false;
					$tokens[$stmtno][] = implode('',$tokarr);
				}
				break;
			}
			
			$tokarr[] = $ch;
			break;
		
		case '`':
			if ($intoken) $tokarr[] = $ch;
		case '(':
		case ')':	
		case '"':
		case "'":
			
			if ($intoken) {
				if (empty($endquote)) {
					$tokens[$stmtno][] = implode('',$tokarr);
					if ($ch == '(') $endquote = ')';
					else $endquote = $ch;
					$quoted = true;
					$intoken = true;
					$tokarr = array();
				} else if ($endquote == $ch) {
					$ch2 = substr($args,$pos+1,1);
					if ($ch2 == $endquote) {
						$pos += 1;
						$tokarr[] = $ch2;
					} else {
						$quoted = false;
						$intoken = false;
						$tokens[$stmtno][] = implode('',$tokarr);
						$endquote = '';
					}
				} else
					$tokarr[] = $ch;
					
			}else {
			
				if ($ch == '(') $endquote = ')';
				else $endquote = $ch;
				$quoted = true;
				$intoken = true;
				$tokarr = array();
				if ($ch == '`') $tokarr[] = '`';
			}
			break;
			
		default:
			
			if (!$intoken) {
				if ($ch == $endstmtchar) {
					$stmtno += 1;
					$tokens[$stmtno] = array();
					break;
				}
			
				$intoken = true;
				$quoted = false;
				$endquote = false;
				$tokarr = array();
	
			}
			
			if ($quoted) $tokarr[] = $ch;
			else if (ctype_alnum($ch) || strpos($tokenchars,$ch) !== false) $tokarr[] = $ch;
			else {
				if ($ch == $endstmtchar) {			
					$tokens[$stmtno][] = implode('',$tokarr);
					$stmtno += 1;
					$tokens[$stmtno] = array();
					$intoken = false;
					$tokarr = array();
					break;
				}
				$tokens[$stmtno][] = implode('',$tokarr);
				$tokens[$stmtno][] = $ch;
				$intoken = false;
			}
		}
		$pos += 1;
	}
	if ($intoken) $tokens[$stmtno][] = implode('',$tokarr);
	
	return $tokens;
}


class ADODB_DataDict {
	var $connection;
	var $debug = false;
	var $dropTable = 'DROP TABLE %s';
	var $renameTable = 'RENAME TABLE %s TO %s'; 
	var $dropIndex = 'DROP INDEX %s';
	var $addCol = ' ADD';
	var $alterCol = ' ALTER COLUMN';
	var $dropCol = ' DROP COLUMN';
	var $renameColumn = 'ALTER TABLE %s RENAME COLUMN %s TO %s';	// table, old-column, new-column, column-definitions (not used by default)
	var $nameRegex = '\w';
	var $nameRegexBrackets = 'a-zA-Z0-9_\(\)';
	var $schema = false;
	var $serverInfo = array();
	var $autoIncrement = false;
	var $dataProvider;
	var $invalidResizeTypes4 = array('CLOB','BLOB','TEXT','DATE','TIME'); // for changetablesql
	var $blobSize = 100; 	/// any varchar/char field this size or greater is treated as a blob
							/// in other words, we use a text area for editting.
	
	function GetCommentSQL($table,$col)
	{
		return false;
	}
	
	function SetCommentSQL($table,$col,$cmt)
	{
		return false;
	}
	
	function MetaTables()
	{
		if (!$this->connection->IsConnected()) return array();
		return $this->connection->MetaTables();
	}
	
	function MetaColumns($tab, $upper=true, $schema=false)
	{
		if (!$this->connection->IsConnected()) return array();
		return $this->connection->MetaColumns($this->TableName($tab), $upper, $schema);
	}
	
	function MetaPrimaryKeys($tab,$owner=false,$intkey=false)
	{
		if (!$this->connection->IsConnected()) return array();
		return $this->connection->MetaPrimaryKeys($this->TableName($tab), $owner, $intkey);
	}
	
	function MetaIndexes($table, $primary = false, $owner = false)
	{
		if (!$this->connection->IsConnected()) return array();
		return $this->connection->MetaIndexes($this->TableName($table), $primary, $owner);
	}
	
	function MetaType($t,$len=-1,$fieldobj=false)
	{		
		static $typeMap = array(
		'VARCHAR' => 'C',
		'VARCHAR2' => 'C',
		'CHAR' => 'C',
		'C' => 'C',
		'STRING' => 'C',
		'NCHAR' => 'C',
		'NVARCHAR' => 'C',
		'VARYING' => 'C',
		'BPCHAR' => 'C',
		'CHARACTER' => 'C',
		'INTERVAL' => 'C',  # Postgres
		'MACADDR' => 'C', # postgres
		##
		'LONGCHAR' => 'X',
		'TEXT' => 'X',
		'NTEXT' => 'X',
		'M' => 'X',
		'X' => 'X',
		'CLOB' => 'X',
		'NCLOB' => 'X',
		'LVARCHAR' => 'X',
		##
		'BLOB' => 'B',
		'IMAGE' => 'B',
		'BINARY' => 'B',
		'VARBINARY' => 'B',
		'LONGBINARY' => 'B',
		'B' => 'B',
		##
		'YEAR' => 'D', // mysql
		'DATE' => 'D',
		'D' => 'D',
		##
		'UNIQUEIDENTIFIER' => 'C', # MS SQL Server
		##
		'TIME' => 'T',
		'TIMESTAMP' => 'T',
		'DATETIME' => 'T',
		'TIMESTAMPTZ' => 'T',
		'T' => 'T',
		'TIMESTAMP WITHOUT TIME ZONE' => 'T', // postgresql
		##
		'BOOL' => 'L',
		'BOOLEAN' => 'L', 
		'BIT' => 'L',
		'L' => 'L',
		##
		'COUNTER' => 'R',
		'R' => 'R',
		'SERIAL' => 'R', // ifx
		'INT IDENTITY' => 'R',
		##
		'INT' => 'I',
		'INT2' => 'I',
		'INT4' => 'I',
		'INT8' => 'I',
		'INTEGER' => 'I',
		'INTEGER UNSIGNED' => 'I',
		'SHORT' => 'I',
		'TINYINT' => 'I',
		'SMALLINT' => 'I',
		'I' => 'I',
		##
		'LONG' => 'N', // interbase is numeric, oci8 is blob
		'BIGINT' => 'N', // this is bigger than PHP 32-bit integers
		'DECIMAL' => 'N',
		'DEC' => 'N',
		'REAL' => 'N',
		'DOUBLE' => 'N',
		'DOUBLE PRECISION' => 'N',
		'SMALLFLOAT' => 'N',
		'FLOAT' => 'N',
		'NUMBER' => 'N',
		'NUM' => 'N',
		'NUMERIC' => 'N',
		'MONEY' => 'N',
		
		## informix 9.2
		'SQLINT' => 'I', 
		'SQLSERIAL' => 'I', 
		'SQLSMINT' => 'I', 
		'SQLSMFLOAT' => 'N', 
		'SQLFLOAT' => 'N', 
		'SQLMONEY' => 'N', 
		'SQLDECIMAL' => 'N', 
		'SQLDATE' => 'D', 
		'SQLVCHAR' => 'C', 
		'SQLCHAR' => 'C', 
		'SQLDTIME' => 'T', 
		'SQLINTERVAL' => 'N', 
		'SQLBYTES' => 'B', 
		'SQLTEXT' => 'X',
		 ## informix 10
		"SQLINT8" => 'I8',
		"SQLSERIAL8" => 'I8',
		"SQLNCHAR" => 'C',
		"SQLNVCHAR" => 'C',
		"SQLLVARCHAR" => 'X',
		"SQLBOOL" => 'L'
		);
		
		if (!$this->connection->IsConnected()) {
			$t = strtoupper($t);
			if (isset($typeMap[$t])) return $typeMap[$t];
			return 'N';
		}
		return $this->connection->MetaType($t,$len,$fieldobj);
	}
	
	function NameQuote($name = NULL,$allowBrackets=false)
	{
		if (!is_string($name)) {
			return FALSE;
		}
		
		$name = trim($name);
		
		if ( !is_object($this->connection) ) {
			return $name;
		}
		
		$quote = $this->connection->nameQuote;
		
		// if name is of the form `name`, quote it
		if ( preg_match('/^`(.+)`$/', $name, $matches) ) {
			return $quote . $matches[1] . $quote;
		}
		
		// if name contains special characters, quote it
		$regex = ($allowBrackets) ? $this->nameRegexBrackets : $this->nameRegex;
		
		if ( !preg_match('/^[' . $regex . ']+$/', $name) ) {
			return $quote . $name . $quote;
		}
		
		return $name;
	}
	
	function TableName($name)
	{
		if ( $this->schema ) {
			return $this->NameQuote($this->schema) .'.'. $this->NameQuote($name);
		}
		return $this->NameQuote($name);
	}
	
	// Executes the sql array returned by GetTableSQL and GetIndexSQL
	function ExecuteSQLArray($sql, $continueOnError = true)
	{
		$rez = 2;
		$conn = $this->connection;
		$saved = $conn->debug;
		foreach($sql as $line) {
			
			if ($this->debug) $conn->debug = true;
			$ok = $conn->Execute($line);
			$conn->debug = $saved;
			if (!$ok) {
				if ($this->debug) ADOConnection::outp($conn->ErrorMsg());
				if (!$continueOnError) return 0;
				$rez = 1;
			}
		}
		return $rez;
	}
	
	/**
	 	Returns the actual type given a character code.
		
		C:  varchar
		X:  CLOB (character large object) or largest varchar size if CLOB is not supported
		C2: Multibyte varchar
		X2: Multibyte CLOB
		
		B:  BLOB (binary large object)
		
		D:  Date
		T:  Date-time 
		L:  Integer field suitable for storing booleans (0 or 1)
		I:  Integer
		F:  Floating point number
		N:  Numeric or decimal number
	*/
	
	function ActualType($meta)
	{
		return $meta;
	}
	
	function CreateDatabase($dbname,$options=false)
	{
		$options = $this->_Options($options);
		$sql = array();
		
		$s = 'CREATE DATABASE ' . $this->NameQuote($dbname);
		if (isset($options[$this->upperName]))
			$s .= ' '.$options[$this->upperName];
		
		$sql[] = $s;
		return $sql;
	}
	
	/*
	 Generates the SQL to create index. Returns an array of sql strings.
	*/
	function CreateIndexSQL($idxname, $tabname, $flds, $idxoptions = false)
	{
		if (!is_array($flds)) {
			$flds = explode(',',$flds);
		}
		
		foreach($flds as $key => $fld) {
			# some indexes can use partial fields, eg. index first 32 chars of "name" with NAME(32)
			$flds[$key] = $this->NameQuote($fld,$allowBrackets=true);
		}
		
		return $this->_IndexSQL($this->NameQuote($idxname), $this->TableName($tabname), $flds, $this->_Options($idxoptions));
	}
	
	function DropIndexSQL ($idxname, $tabname = NULL)
	{
		return array(sprintf($this->dropIndex, $this->NameQuote($idxname), $this->TableName($tabname)));
	}
	
	function SetSchema($schema)
	{
		$this->schema = $schema;
	}
	
	function AddColumnSQL($tabname, $flds)
	{
		$tabname = $this->TableName ($tabname);
		$sql = array();
		list($lines,$pkey,$idxs) = $this->_GenFields($flds);
		// genfields can return FALSE at times
		if ($lines  == null) $lines = array();
		$alter = 'ALTER TABLE ' . $tabname . $this->addCol . ' ';
		foreach($lines as $v) {
			$sql[] = $alter . $v;
		}
		if (is_array($idxs)) {
			foreach($idxs as $idx => $idxdef) {
				$sql_idxs = $this->CreateIndexSql($idx, $tabname, $idxdef['cols'], $idxdef['opts']);
				$sql = array_merge($sql, $sql_idxs);
			}
		}
		return $sql;
	}
	
	/**
	 * Change the definition of one column
	 *
	 * As some DBM's can't do that on there own, you need to supply the complete defintion of the new table,
	 * to allow, recreating the table and copying the content over to the new table
	 * @param string $tabname table-name
	 * @param string $flds column-name and type for the changed column
	 * @param string $tableflds='' complete defintion of the new table, eg. for postgres, default ''
	 * @param array/string $tableoptions='' options for the new table see CreateTableSQL, default ''
	 * @return array with SQL strings
	 */
	function AlterColumnSQL($tabname, $flds, $tableflds='',$tableoptions='')
	{
		$tabname = $this->TableName ($tabname);
		$sql = array();
		list($lines,$pkey,$idxs) = $this->_GenFields($flds);
		// genfields can return FALSE at times
		if ($lines == null) $lines = array();
		$alter = 'ALTER TABLE ' . $tabname . $this->alterCol . ' ';
		foreach($lines as $v) {
			$sql[] = $alter . $v;
		}
		if (is_array($idxs)) {
			foreach($idxs as $idx => $idxdef) {
				$sql_idxs = $this->CreateIndexSql($idx, $tabname, $idxdef['cols'], $idxdef['opts']);
				$sql = array_merge($sql, $sql_idxs);
			}

		}
		return $sql;
	}
	
	/**
	 * Rename one column
	 *
	 * Some DBM's can only do this together with changeing the type of the column (even if that stays the same, eg. mysql)
	 * @param string $tabname table-name
	 * @param string $oldcolumn column-name to be renamed
	 * @param string $newcolumn new column-name
	 * @param string $flds='' complete column-defintion-string like for AddColumnSQL, only used by mysql atm., default=''
	 * @return array with SQL strings
	 */
	function RenameColumnSQL($tabname,$oldcolumn,$newcolumn,$flds='')
	{
		$tabname = $this->TableName ($tabname);
		if ($flds) {
			list($lines,$pkey,$idxs) = $this->_GenFields($flds);
			// genfields can return FALSE at times
			if ($lines == null) $lines = array();
			list(,$first) = each($lines);
			list(,$column_def) = split("[\t ]+",$first,2);
		}
		return array(sprintf($this->renameColumn,$tabname,$this->NameQuote($oldcolumn),$this->NameQuote($newcolumn),$column_def));
	}
		
	/**
	 * Drop one column
	 *
	 * Some DBM's can't do that on there own, you need to supply the complete defintion of the new table,
	 * to allow, recreating the table and copying the content over to the new table
	 * @param string $tabname table-name
	 * @param string $flds column-name and type for the changed column
	 * @param string $tableflds='' complete defintion of the new table, eg. for postgres, default ''
	 * @param array/string $tableoptions='' options for the new table see CreateTableSQL, default ''
	 * @return array with SQL strings
	 */
	function DropColumnSQL($tabname, $flds, $tableflds='',$tableoptions='')
	{
		$tabname = $this->TableName ($tabname);
		if (!is_array($flds)) $flds = explode(',',$flds);
		$sql = array();
		$alter = 'ALTER TABLE ' . $tabname . $this->dropCol . ' ';
		foreach($flds as $v) {
			$sql[] = $alter . $this->NameQuote($v);
		}
		return $sql;
	}
	
	function DropTableSQL($tabname)
	{
		return array (sprintf($this->dropTable, $this->TableName($tabname)));
	}
	
	function RenameTableSQL($tabname,$newname)
	{
		return array (sprintf($this->renameTable, $this->TableName($tabname),$this->TableName($newname)));
	}	
	
	/**
	 Generate the SQL to create table. Returns an array of sql strings.
	*/
	function CreateTableSQL($tabname, $flds, $tableoptions=array())
	{
		list($lines,$pkey,$idxs) = $this->_GenFields($flds, true);
		// genfields can return FALSE at times
		if ($lines == null) $lines = array();
		
		$taboptions = $this->_Options($tableoptions);
		$tabname = $this->TableName ($tabname);
		$sql = $this->_TableSQL($tabname,$lines,$pkey,$taboptions);
		
		// ggiunta - 2006/10/12 - KLUDGE:
        // if we are on autoincrement, and table options includes REPLACE, the
        // autoincrement sequence has already been dropped on table creation sql, so
        // we avoid passing REPLACE to trigger creation code. This prevents
        // creating sql that double-drops the sequence
        if ($this->autoIncrement && isset($taboptions['REPLACE']))
        	unset($taboptions['REPLACE']);
		$tsql = $this->_Triggers($tabname,$taboptions);
		foreach($tsql as $s) $sql[] = $s;
		
		if (is_array($idxs)) {
			foreach($idxs as $idx => $idxdef) {
				$sql_idxs = $this->CreateIndexSql($idx, $tabname,  $idxdef['cols'], $idxdef['opts']);
				$sql = array_merge($sql, $sql_idxs);
			}
		}

		return $sql;
	}
	
	function _GenFields($flds,$widespacing=false)
	{
		if (is_string($flds)) {
			$padding = '     ';
			$txt = $flds.$padding;
			$flds = array();
			$flds0 = Lens_ParseArgs($txt,',');
			$hasparam = false;
			foreach($flds0 as $f0) {
				$f1 = array();
				foreach($f0 as $token) {
					switch (strtoupper($token)) {
					case 'INDEX':
						$f1['INDEX'] = '';
						// fall through intentionally
					case 'CONSTRAINT':
					case 'DEFAULT': 
						$hasparam = $token;
						break;
					default:
						if ($hasparam) $f1[$hasparam] = $token;
						else $f1[] = $token;
						$hasparam = false;
						break;
					}
				}
				// 'index' token without a name means single column index: name it after column
				if (array_key_exists('INDEX', $f1) && $f1['INDEX'] == '') {
					$f1['INDEX'] = isset($f0['NAME']) ? $f0['NAME'] : $f0[0];
					// check if column name used to create an index name was quoted
					if (($f1['INDEX'][0] == '"' || $f1['INDEX'][0] == "'" || $f1['INDEX'][0] == "`") &&
						($f1['INDEX'][0] == substr($f1['INDEX'], -1))) {
						$f1['INDEX'] = $f1['INDEX'][0].'idx_'.substr($f1['INDEX'], 1, -1).$f1['INDEX'][0];
					}
					else
						$f1['INDEX'] = 'idx_'.$f1['INDEX'];
				}
				// reset it, so we don't get next field 1st token as INDEX...
				$hasparam = false;

				$flds[] = $f1;
				
			}
		}
		$this->autoIncrement = false;
		$lines = array();
		$pkey = array();
		$idxs = array();
		foreach($flds as $fld) {
			$fld = _array_change_key_case($fld);
			
			$fname = false;
			$fdefault = false;
			$fautoinc = false;
			$ftype = false;
			$fsize = false;
			$fprec = false;
			$fprimary = false;
			$fnoquote = false;
			$fdefts = false;
			$fdefdate = false;
			$fconstraint = false;
			$fnotnull = false;
			$funsigned = false;
			$findex = '';
			$funiqueindex = false;
			
			//-----------------
			// Parse attributes
			foreach($fld as $attr => $v) {
				if ($attr == 2 && is_numeric($v)) $attr = 'SIZE';
				else if (is_numeric($attr) && $attr > 1 && !is_numeric($v)) $attr = strtoupper($v);
				
				switch($attr) {
				case '0':
				case 'NAME': 	$fname = $v; break;
				case '1':
				case 'TYPE': 	$ty = $v; $ftype = $this->ActualType(strtoupper($v)); break;
				
				case 'SIZE': 	
								$dotat = strpos($v,'.'); if ($dotat === false) $dotat = strpos($v,',');
								if ($dotat === false) $fsize = $v;
								else {
									$fsize = substr($v,0,$dotat);
									$fprec = substr($v,$dotat+1);
								}
								break;
				case 'UNSIGNED': $funsigned = true; break;
				case 'AUTOINCREMENT':
				case 'AUTO':	$fautoinc = true; $fnotnull = true; break;
				case 'KEY':
                // a primary key col can be non unique in itself (if key spans many cols...)
				case 'PRIMARY':	$fprimary = $v; $fnotnull = true; /*$funiqueindex = true;*/ break;
				case 'DEF':
				case 'DEFAULT': $fdefault = $v; break;
				case 'NOTNULL': $fnotnull = $v; break;
				case 'NOQUOTE': $fnoquote = $v; break;
				case 'DEFDATE': $fdefdate = $v; break;
				case 'DEFTIMESTAMP': $fdefts = $v; break;
				case 'CONSTRAINT': $fconstraint = $v; break;
				// let INDEX keyword create a 'very standard' index on column
				case 'INDEX': $findex = $v; break;
				case 'UNIQUE': $funiqueindex = true; break;
				} //switch
			} // foreach $fld
			
			//--------------------
			// VALIDATE FIELD INFO
			if (!strlen($fname)) {
				if ($this->debug) ADOConnection::outp("Undefined NAME");
				return false;
			}
			
			$fid = strtoupper(preg_replace('/^`(.+)`$/', '$1', $fname));
			$fname = $this->NameQuote($fname);
			
			if (!strlen($ftype)) {
				if ($this->debug) ADOConnection::outp("Undefined TYPE for field '$fname'");
				return false;
			} else {
				$ftype = strtoupper($ftype);
			}
			
			$ftype = $this->_GetSize($ftype, $ty, $fsize, $fprec);
			
			if ($ty == 'X' || $ty == 'X2' || $ty == 'B') $fnotnull = false; // some blob types do not accept nulls
			
			if ($fprimary) $pkey[] = $fname;
			
			// some databases do not allow blobs to have defaults
			if ($ty == 'X') $fdefault = false;
			
			// build list of indexes
			if ($findex != '') {
				if (array_key_exists($findex, $idxs)) {
					$idxs[$findex]['cols'][] = ($fname);
					if (in_array('UNIQUE', $idxs[$findex]['opts']) != $funiqueindex) {
						if ($this->debug) ADOConnection::outp("Index $findex defined once UNIQUE and once not");
					}
					if ($funiqueindex && !in_array('UNIQUE', $idxs[$findex]['opts']))
						$idxs[$findex]['opts'][] = 'UNIQUE';
				}
				else
				{
					$idxs[$findex] = array();
					$idxs[$findex]['cols'] = array($fname);
					if ($funiqueindex)
						$idxs[$findex]['opts'] = array('UNIQUE');
					else
						$idxs[$findex]['opts'] = array();
				}
			}

			//--------------------
			// CONSTRUCT FIELD SQL
			if ($fdefts) {
				if (substr($this->connection->databaseType,0,5) == 'mysql') {
					$ftype = 'TIMESTAMP';
				} else {
					$fdefault = $this->connection->sysTimeStamp;
				}
			} else if ($fdefdate) {
				if (substr($this->connection->databaseType,0,5) == 'mysql') {
					$ftype = 'TIMESTAMP';
				} else {
					$fdefault = $this->connection->sysDate;
				}
			} else if ($fdefault !== false && !$fnoquote) {
				if ($ty == 'C' or $ty == 'X' or 
					( substr($fdefault,0,1) != "'" && !is_numeric($fdefault))) {

					if (($ty == 'D' || $ty == 'T') && strtolower($fdefault) != 'null') {
						// convert default date into database-aware code
						if ($ty == 'T')
						{
							$fdefault = $this->connection->DBTimeStamp($fdefault);
						}
						else
						{
							$fdefault = $this->connection->DBDate($fdefault);
						}
					}
					else
					if (strlen($fdefault) != 1 && substr($fdefault,0,1) == ' ' && substr($fdefault,strlen($fdefault)-1) == ' ') 
						$fdefault = trim($fdefault);
					else if (strtolower($fdefault) != 'null')
						$fdefault = $this->connection->qstr($fdefault);
				}
			}
			$suffix = $this->_CreateSuffix($fname,$ftype,$fnotnull,$fdefault,$fautoinc,$fconstraint,$funsigned);
			
			// add index creation
			if ($widespacing) $fname = str_pad($fname,24);
			
			 // check for field names appearing twice
            if (array_key_exists($fid, $lines)) {
            	 ADOConnection::outp("Field '$fname' defined twice");
            }
			
			$lines[$fid] = $fname.' '.$ftype.$suffix;
			
			if ($fautoinc) $this->autoIncrement = true;
		} // foreach $flds
		
		return array($lines,$pkey,$idxs);
	}

	/**
		 GENERATE THE SIZE PART OF THE DATATYPE
			$ftype is the actual type
			$ty is the type defined originally in the DDL
	*/
	function _GetSize($ftype, $ty, $fsize, $fprec)
	{
		if (strlen($fsize) && $ty != 'X' && $ty != 'B' && strpos($ftype,'(') === false) {
			$ftype .= "(".$fsize;
			if (strlen($fprec)) $ftype .= ",".$fprec;
			$ftype .= ')';
		}
		return $ftype;
	}
	
	
	// return string must begin with space
	function _CreateSuffix($fname,$ftype,$fnotnull,$fdefault,$fautoinc,$fconstraint)
	{	
		$suffix = '';
		if (strlen($fdefault)) $suffix .= " DEFAULT $fdefault";
		if ($fnotnull) $suffix .= ' NOT NULL';
		if ($fconstraint) $suffix .= ' '.$fconstraint;
		return $suffix;
	}
	
	function _IndexSQL($idxname, $tabname, $flds, $idxoptions)
	{
		$sql = array();
		
		if ( isset($idxoptions['REPLACE']) || isset($idxoptions['DROP']) ) {
			$sql[] = sprintf ($this->dropIndex, $idxname);
			if ( isset($idxoptions['DROP']) )
				return $sql;
		}
		
		if ( empty ($flds) ) {
			return $sql;
		}
		
		$unique = isset($idxoptions['UNIQUE']) ? ' UNIQUE' : '';
	
		$s = 'CREATE' . $unique . ' INDEX ' . $idxname . ' ON ' . $tabname . ' ';
		
		if ( isset($idxoptions[$this->upperName]) )
			$s .= $idxoptions[$this->upperName];
		
		if ( is_array($flds) )
			$flds = implode(', ',$flds);
		$s .= '(' . $flds . ')';
		$sql[] = $s;
		
		return $sql;
	}
	
	function _DropAutoIncrement($tabname)
	{
		return false;
	}
	
	function _TableSQL($tabname,$lines,$pkey,$tableoptions)
	{
		$sql = array();
		
		if (isset($tableoptions['REPLACE']) || isset ($tableoptions['DROP'])) {
			$sql[] = sprintf($this->dropTable,$tabname);
			if ($this->autoIncrement) {
				$sInc = $this->_DropAutoIncrement($tabname);
				if ($sInc) $sql[] = $sInc;
			}
			if ( isset ($tableoptions['DROP']) ) {
				return $sql;
			}
		}
		$s = "CREATE TABLE $tabname (\n";
		$s .= implode(",\n", $lines);
		if (sizeof($pkey)>0) {
			$s .= ",\n                 PRIMARY KEY (";
			$s .= implode(", ",$pkey).")";
		}
		if (isset($tableoptions['CONSTRAINTS'])) 
			$s .= "\n".$tableoptions['CONSTRAINTS'];
		
		if (isset($tableoptions[$this->upperName.'_CONSTRAINTS'])) 
			$s .= "\n".$tableoptions[$this->upperName.'_CONSTRAINTS'];
		
		$s .= "\n)";
		if (isset($tableoptions[$this->upperName])) $s .= $tableoptions[$this->upperName];
		$sql[] = $s;
		
		return $sql;
	}
	
	/**
		GENERATE TRIGGERS IF NEEDED
		used when table has auto-incrementing field that is emulated using triggers
	*/
	function _Triggers($tabname,$taboptions)
	{
		return array();
	}
	
	/**
		Sanitize options, so that array elements with no keys are promoted to keys
	*/
	function _Options($opts)
	{
		if (!is_array($opts)) return array();
		$newopts = array();
		foreach($opts as $k => $v) {
			if (is_numeric($k)) $newopts[strtoupper($v)] = $v;
			else $newopts[strtoupper($k)] = $v;
		}
		return $newopts;
	}
	
	/**
	"Florian Buzin [ easywe ]" <florian.buzin#easywe.de>
	
	This function changes/adds new fields to your table. You don't
	have to know if the col is new or not. It will check on its own.
	*/
	function ChangeTableSQL($tablename, $flds, $tableoptions = false)
	{
	global $ADODB_FETCH_MODE;
	
		$save = $ADODB_FETCH_MODE;
		$ADODB_FETCH_MODE = ADODB_FETCH_ASSOC;
		if ($this->connection->fetchMode !== false) $savem = $this->connection->SetFetchMode(false);
		
		// check table exists
		$save_handler = $this->connection->raiseErrorFn;
		$this->connection->raiseErrorFn = '';
		$cols = $this->MetaColumns($tablename);
		$this->connection->raiseErrorFn = $save_handler;
		
		if (isset($savem)) $this->connection->SetFetchMode($savem);
		$ADODB_FETCH_MODE = $save;
		
		if ( empty($cols)) { 
			return $this->CreateTableSQL($tablename, $flds, $tableoptions);
		}
		
		if (is_array($flds)) {
		// Cycle through the update fields, comparing
		// existing fields to fields to update.
		// if the Metatype and size is exactly the
		// same, ignore - by Mark Newham
			$holdflds = array();
			foreach($flds as $k=>$v) {
				if ( isset($cols[$k]) && is_object($cols[$k]) ) {
					// If already not allowing nulls, then don't change
					$obj = $cols[$k];
					if (isset($obj->not_null) && $obj->not_null)
						$v = str_replace('NOT NULL','',$v);

					$c = $cols[$k];
					$ml = $c->max_length;
					$mt = $this->MetaType($c->type,$ml);
					if ($ml == -1) $ml = '';
					if ($mt == 'X') $ml = $v['SIZE'];
					if (($mt != $v['TYPE']) ||  $ml != $v['SIZE']) {
						$holdflds[$k] = $v;
					}
				} else {
					$holdflds[$k] = $v;
				}		
			}
			$flds = $holdflds;
		}
	

		// already exists, alter table instead
		list($lines,$pkey,$idxs) = $this->_GenFields($flds);
		// genfields can return FALSE at times
		if ($lines == null) $lines = array();
		$alter = 'ALTER TABLE ' . $this->TableName($tablename);
		$sql = array();

		foreach ( $lines as $id => $v ) {
			if ( isset($cols[$id]) && is_object($cols[$id]) ) {
			
				$flds = Lens_ParseArgs($v,',');
				
				//  We are trying to change the size of the field, if not allowed, simply ignore the request.
				// $flds[1] holds the type, $flds[2] holds the size -postnuke addition
				if ($flds && in_array(strtoupper(substr($flds[0][1],0,4)),$this->invalidResizeTypes4)
				 && (isset($flds[0][2]) && is_numeric($flds[0][2]))) {
					if ($this->debug) ADOConnection::outp(sprintf("<h3>%s cannot be changed to %s currently</h3>", $flds[0][0], $flds[0][1]));
					#echo "<h3>$this->alterCol cannot be changed to $flds currently</h3>";
					continue;	 
	 			}
				$sql[] = $alter . $this->alterCol . ' ' . $v;
			} else {
				$sql[] = $alter . $this->addCol . ' ' . $v;
			}
		}
		
		return $sql;
	}
} // class
?>