database.php

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		$this->_offset	= (int) $offset;
	}

	/**
	 * This function replaces a string identifier <var>$prefix</var> with the
	 * string held is the <var>_table_prefix</var> class variable.
	 *
	 * @access public
	 * @param string The SQL query
	 * @param string The common table prefix
	 */
	function replacePrefix( $sql, $prefix='#__' )
	{
		$sql = trim( $sql );

		$escaped = false;
		$quoteChar = '';

		$n = strlen( $sql );

		$startPos = 0;
		$literal = '';
		while ($startPos < $n) {
			$ip = strpos($sql, $prefix, $startPos);
			if ($ip === false) {
				break;
			}

			$j = strpos( $sql, "'", $startPos );
			$k = strpos( $sql, '"', $startPos );
			if (($k !== FALSE) && (($k < $j) || ($j === FALSE))) {
				$quoteChar	= '"';
				$j			= $k;
			} else {
				$quoteChar	= "'";
			}

			if ($j === false) {
				$j = $n;
			}

			$literal .= str_replace( $prefix, $this->_table_prefix,substr( $sql, $startPos, $j - $startPos ) );
			$startPos = $j;

			$j = $startPos + 1;

			if ($j >= $n) {
				break;
			}

			// quote comes first, find end of quote
			while (TRUE) {
				$k = strpos( $sql, $quoteChar, $j );
				$escaped = false;
				if ($k === false) {
					break;
				}
				$l = $k - 1;
				while ($l >= 0 && $sql{$l} == '\\') {
					$l--;
					$escaped = !$escaped;
				}
				if ($escaped) {
					$j	= $k+1;
					continue;
				}
				break;
			}
			if ($k === FALSE) {
				// error in the query - no end quote; ignore it
				break;
			}
			$literal .= substr( $sql, $startPos, $k - $startPos + 1 );
			$startPos = $k+1;
		}
		if ($startPos < $n) {
			$literal .= substr( $sql, $startPos, $n - $startPos );
		}
		return $literal;
	}

	/**
	 * Get the active query
	 *
	 * @access public
	 * @return string The current value of the internal SQL vairable
	 */
	function getQuery()
	{
		return $this->_sql;
	}

	/**
	 * Execute the query
	 *
	 * @abstract
	 * @access public
	 * @return mixed A database resource if successful, FALSE if not.
	 */
	function query()
	{
		return;
	}

	/**
	 * Get the affected rows by the most recent query
	 *
	 * @abstract
	 * @access public
	 * @return int The number of affected rows in the previous operation
	 * @since 1.0.5
	 */
	function getAffectedRows()
	{
		return;
	}

	/**
	* Execute a batch query
	*
	* @abstract
	* @access public
	* @return mixed A database resource if successful, FALSE if not.
	*/
	function queryBatch( $abort_on_error=true, $p_transaction_safe = false)
	{
		return false;
	}

	/**
	 * Diagnostic function
	 *
	 * @abstract
	 * @access public
	 */
	function explain()
	{
		return;
	}

	/**
	 * Get the number of rows returned by the most recent query
	 *
	 * @abstract
	 * @access public
	 * @param object Database resource
	 * @return int The number of rows
	 */
	function getNumRows( $cur=null )
	{
		return;
	}

	/**
	 * This method loads the first field of the first row returned by the query.
	 *
	 * @abstract
	 * @access public
	 * @return The value returned in the query or null if the query failed.
	 */
	function loadResult()
	{
		return;
	}

	/**
	 * Load an array of single field results into an array
	 *
	 * @abstract
	 */
	function loadResultArray($numinarray = 0)
	{
		return;
	}

	/**
	* Fetch a result row as an associative array
	*
	* @abstract
	*/
	function loadAssoc()
	{
		return;
	}

	/**
	 * Load a associactive list of database rows
	 *
	 * @abstract
	 * @access public
	 * @param string The field name of a primary key
	 * @return array If key is empty as sequential list of returned records.
	 */
	function loadAssocList( $key='' )
	{
		return;
	}

	/**
	 * This global function loads the first row of a query into an object
	 *
	 *
	 * @abstract
	 * @access public
	 * @param object
	 */
	function loadObject( )
	{
		return;
	}

	/**
	* Load a list of database objects
	*
	* @abstract
	* @access public
	* @param string The field name of a primary key
	* @return array If <var>key</var> is empty as sequential list of returned records.

	* If <var>key</var> is not empty then the returned array is indexed by the value
	* the database key.  Returns <var>null</var> if the query fails.
	*/
	function loadObjectList( $key='' )
	{
		return;
	}

	/**
	 * Load the first row returned by the query
	 *
	 * @abstract
	 * @access public
	 * @return The first row of the query.
	 */
	function loadRow()
	{
		return;
	}

	/**
	* Load a list of database rows (numeric column indexing)
	*
	* If <var>key</var> is not empty then the returned array is indexed by the value
	* the database key.  Returns <var>null</var> if the query fails.
	*
	* @abstract
	* @access public
	* @param string The field name of a primary key
	* @return array
	*/
	function loadRowList( $key='' )
	{
		return;
	}

	/**
	 * Inserts a row into a table based on an objects properties
	 * @param	string	The name of the table
	 * @param	object	An object whose properties match table fields
	 * @param	string	The name of the primary key. If provided the object property is updated.
	 */
	function insertObject( $table, &$object, $keyName = NULL )
	{
		return;
	}

	/**
	 * Update an object in the database
	 *
	 * @abstract
	 * @access public
	 * @param string
	 * @param object
	 * @param string
	 * @param boolean
	 */
	function updateObject( $table, &$object, $keyName, $updateNulls=true )
	{
		return;
	}

	/**
	 * Print out an error statement
	 *
	 * @param boolean If TRUE, displays the last SQL statement sent to the database
	 * @return string A standised error message
	 */
	function stderr( $showSQL = false )
	{
		if ( $this->_errorNum != 0 ) {
			return "DB function failed with error number $this->_errorNum"
			."<br /><font color=\"red\">$this->_errorMsg</font>"
			.($showSQL ? "<br />SQL = <pre>$this->_sql</pre>" : '');
		} else {
			return "DB function reports no errors";
		}
	}

	/**
	 * Get the ID generated from the previous INSERT operation
	 *
	 * @abstract
	 * @access public
	 * @return mixed
	 */
	function insertid()
	{
		return;
	}

	/**
	 * Get the database collation
	 *
	 * @abstract
	 * @access public
	 * @return string Collation in use
	 */
	function getCollation()
	{
		return;
	}

	/**
	 * Get the version of the database connector
	 *
	 * @abstract
	 */
	function getVersion()
	{
		return 'Not available for this connector';
	}

	/**
	 * List tables in a database
	 *
	 * @abstract
	 * @access public
	 * @return array A list of all the tables in the database
	 */
	function getTableList()
	{
		return;
	}

	/**
	 * Shows the CREATE TABLE statement that creates the given tables
	 *
	 * @abstract
	 * @access	public
	 * @param 	array|string 	A table name or a list of table names
	 * @return 	array A list the create SQL for the tables
	 */
	function getTableCreate( $tables )
	{
		return;
	}

	/**
	 * Retrieves information about the given tables
	 *
	 * @abstract
	 * @access	public
	 * @param 	array|string 	A table name or a list of table names
	 * @param	boolean			Only return field types, default true
	 * @return	array An array of fields by table
	 */
	function getTableFields( $tables, $typeonly = true )
	{
		return;
	}

	// ----
	// ADODB Compatibility Functions
	// ----

	/**
	* Get a quoted database escaped string
	*
	* @param	string	A string
	* @param	boolean	Default true to escape string, false to leave the string unchanged
	* @return	string
	* @access public
	*/
	function Quote( $text, $escaped = true )
	{
		return '\''.($escaped ? $this->getEscaped( $text ) : $text).'\'';
	}

	/**
	 * ADODB compatability function
	 *
	 * @access	public
	 * @param	string SQL
	 * @since	1.5
	 */
	function GetCol( $query )
	{
		$this->setQuery( $query );
		return $this->loadResultArray();
	}

	/**
	 * ADODB compatability function
	 *
	 * @access	public
	 * @param	string SQL
	 * @return	object
	 * @since	1.5
	 */
	function Execute( $query )
	{
		jimport( 'joomla.database.recordset' );

		$query = trim( $query );
		$this->setQuery( $query );
		if (eregi( '^select', $query )) {
			$result = $this->loadRowList();
			return new JRecordSet( $result );
		} else {
			$result = $this->query();
			if ($result === false) {
				return false;
			} else {
				return new JRecordSet( array() );
			}
		}
	}

	/**
	 * ADODB compatability function
	 *
	 * @access public
	 * @since 1.5
	 */
	function SelectLimit( $query, $count, $offset=0 )
	{
		jimport( 'joomla.database.recordset' );

		$this->setQuery( $query, $offset, $count );
		$result = $this->loadRowList();
		return new JRecordSet( $result );
	}

	/**
	 * ADODB compatability function
	 *
	 * @access public
	 * @since 1.5
	 */
	function PageExecute( $sql, $nrows, $page, $inputarr=false, $secs2cache=0 )
	{
		jimport( 'joomla.database.recordset' );

		$this->setQuery( $sql, $page*$nrows, $nrows );
		$result = $this->loadRowList();
		return new JRecordSet( $result );
	}
	/**
	 * ADODB compatability function
	 *
	 * @access public
	 * @param string SQL
	 * @return array
	 * @since 1.5
	 */
	function GetRow( $query )
	{
		$this->setQuery( $query );
		$result = $this->loadRowList();
		return $result[0];
	}

	/**
	 * ADODB compatability function
	 *
	 * @access public
	 * @param string SQL
	 * @return mixed
	 * @since 1.5
	 */
	function GetOne( $query )
	{
		$this->setQuery( $query );
		$result = $this->loadResult();
		return $result;
	}

	/**
	 * ADODB compatability function
	 *
	 * @since 1.5
	 */
	function BeginTrans()
	{
	}

	/**
	 * ADODB compatability function
	 *
	 * @since 1.5
	 */
	function RollbackTrans()
	{
	}

	/**
	 * ADODB compatability function
	 *
	 * @since 1.5
	 */
	function CommitTrans()
	{
	}

	/**
	 * ADODB compatability function
	 *
	 * @since 1.5
	 */
	function ErrorMsg()
	{
		return $this->getErrorMsg();
	}

	/**
	 * ADODB compatability function
	 *
	 * @since 1.5
	 */
	function ErrorNo()
	{
		return $this->getErrorNum();
	}

	/**
	 * ADODB compatability function
	 *
	 * @since 1.5
	 */
	function GenID( $foo1=null, $foo2=null )
	{
		return '0';
	}
}