📄 mysql.php
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* @see DB_common::dropSequence(), DB_common::getSequenceName(),
* DB_mysql::nextID(), DB_mysql::createSequence()
*/
function dropSequence($seq_name)
{
return $this->query('DROP TABLE ' . $this->getSequenceName($seq_name));
}
// }}}
// {{{ _BCsequence()
/**
* Backwards compatibility with old sequence emulation implementation
* (clean up the dupes)
*
* @param string $seqname the sequence name to clean up
*
* @return bool true on success. A DB_Error object on failure.
*
* @access private
*/
function _BCsequence($seqname)
{
// Obtain a user-level lock... this will release any previous
// application locks, but unlike LOCK TABLES, it does not abort
// the current transaction and is much less frequently used.
$result = $this->getOne("SELECT GET_LOCK('${seqname}_lock',10)");
if (DB::isError($result)) {
return $result;
}
if ($result == 0) {
// Failed to get the lock, can't do the conversion, bail
// with a DB_ERROR_NOT_LOCKED error
return $this->mysqlRaiseError(DB_ERROR_NOT_LOCKED);
}
$highest_id = $this->getOne("SELECT MAX(id) FROM ${seqname}");
if (DB::isError($highest_id)) {
return $highest_id;
}
// This should kill all rows except the highest
// We should probably do something if $highest_id isn't
// numeric, but I'm at a loss as how to handle that...
$result = $this->query('DELETE FROM ' . $seqname
. " WHERE id <> $highest_id");
if (DB::isError($result)) {
return $result;
}
// If another thread has been waiting for this lock,
// it will go thru the above procedure, but will have no
// real effect
$result = $this->getOne("SELECT RELEASE_LOCK('${seqname}_lock')");
if (DB::isError($result)) {
return $result;
}
return true;
}
// }}}
// {{{ quoteIdentifier()
/**
* Quotes a string so it can be safely used as a table or column name
*
* MySQL can't handle the backtick character (<kbd>`</kbd>) in
* table or column names.
*
* @param string $str identifier name to be quoted
*
* @return string quoted identifier string
*
* @see DB_common::quoteIdentifier()
* @since Method available since Release 1.6.0
*/
function quoteIdentifier($str)
{
return '`' . $str . '`';
}
// }}}
// {{{ quote()
/**
* @deprecated Deprecated in release 1.6.0
*/
function quote($str)
{
return $this->quoteSmart($str);
}
// }}}
// {{{ escapeSimple()
/**
* Escapes a string according to the current DBMS's standards
*
* @param string $str the string to be escaped
*
* @return string the escaped string
*
* @see DB_common::quoteSmart()
* @since Method available since Release 1.6.0
*/
function escapeSimple($str)
{
if (function_exists('mysql_real_escape_string')) {
return @mysql_real_escape_string($str, $this->connection);
} else {
return @mysql_escape_string($str);
}
}
// }}}
// {{{ modifyQuery()
/**
* Changes a query string for various DBMS specific reasons
*
* This little hack lets you know how many rows were deleted
* when running a "DELETE FROM table" query. Only implemented
* if the DB_PORTABILITY_DELETE_COUNT portability option is on.
*
* @param string $query the query string to modify
*
* @return string the modified query string
*
* @access protected
* @see DB_common::setOption()
*/
function modifyQuery($query)
{
if ($this->options['portability'] & DB_PORTABILITY_DELETE_COUNT) {
// "DELETE FROM table" gives 0 affected rows in MySQL.
// This little hack lets you know how many rows were deleted.
if (preg_match('/^\s*DELETE\s+FROM\s+(\S+)\s*$/i', $query)) {
$query = preg_replace('/^\s*DELETE\s+FROM\s+(\S+)\s*$/',
'DELETE FROM \1 WHERE 1=1', $query);
}
}
return $query;
}
// }}}
// {{{ modifyLimitQuery()
/**
* Adds LIMIT clauses to a query string according to current DBMS standards
*
* @param string $query the query to modify
* @param int $from the row to start to fetching (0 = the first row)
* @param int $count the numbers of rows to fetch
* @param mixed $params array, string or numeric data to be used in
* execution of the statement. Quantity of items
* passed must match quantity of placeholders in
* query: meaning 1 placeholder for non-array
* parameters or 1 placeholder per array element.
*
* @return string the query string with LIMIT clauses added
*
* @access protected
*/
function modifyLimitQuery($query, $from, $count, $params = array())
{
if (DB::isManip($query)) {
return $query . " LIMIT $count";
} else {
return $query . " LIMIT $from, $count";
}
}
// }}}
// {{{ mysqlRaiseError()
/**
* Produces a DB_Error object regarding the current problem
*
* @param int $errno if the error is being manually raised pass a
* DB_ERROR* constant here. If this isn't passed
* the error information gathered from the DBMS.
*
* @return object the DB_Error object
*
* @see DB_common::raiseError(),
* DB_mysql::errorNative(), DB_common::errorCode()
*/
function mysqlRaiseError($errno = null)
{
if ($errno === null) {
if ($this->options['portability'] & DB_PORTABILITY_ERRORS) {
$this->errorcode_map[1022] = DB_ERROR_CONSTRAINT;
$this->errorcode_map[1048] = DB_ERROR_CONSTRAINT_NOT_NULL;
$this->errorcode_map[1062] = DB_ERROR_CONSTRAINT;
} else {
// Doing this in case mode changes during runtime.
$this->errorcode_map[1022] = DB_ERROR_ALREADY_EXISTS;
$this->errorcode_map[1048] = DB_ERROR_CONSTRAINT;
$this->errorcode_map[1062] = DB_ERROR_ALREADY_EXISTS;
}
$errno = $this->errorCode(mysql_errno($this->connection));
}
return $this->raiseError($errno, null, null, null,
@mysql_errno($this->connection) . ' ** ' .
@mysql_error($this->connection));
}
// }}}
// {{{ errorNative()
/**
* Gets the DBMS' native error code produced by the last query
*
* @return int the DBMS' error code
*/
function errorNative()
{
return @mysql_errno($this->connection);
}
// }}}
// {{{ tableInfo()
/**
* Returns information about a table or a result set
*
* @param object|string $result DB_result object from a query or a
* string containing the name of a table.
* While this also accepts a query result
* resource identifier, this behavior is
* deprecated.
* @param int $mode a valid tableInfo mode
*
* @return array an associative array with the information requested.
* A DB_Error object on failure.
*
* @see DB_common::tableInfo()
*/
function tableInfo($result, $mode = null)
{
if (is_string($result)) {
/*
* Probably received a table name.
* Create a result resource identifier.
*/
$id = @mysql_list_fields($this->dsn['database'],
$result, $this->connection);
$got_string = true;
} elseif (isset($result->result)) {
/*
* Probably received a result object.
* Extract the result resource identifier.
*/
$id = $result->result;
$got_string = false;
} else {
/*
* Probably received a result resource identifier.
* Copy it.
* Deprecated. Here for compatibility only.
*/
$id = $result;
$got_string = false;
}
if (!is_resource($id)) {
return $this->mysqlRaiseError(DB_ERROR_NEED_MORE_DATA);
}
if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE) {
$case_func = 'strtolower';
} else {
$case_func = 'strval';
}
$count = @mysql_num_fields($id);
$res = array();
if ($mode) {
$res['num_fields'] = $count;
}
for ($i = 0; $i < $count; $i++) {
$res[$i] = array(
'table' => $case_func(@mysql_field_table($id, $i)),
'name' => $case_func(@mysql_field_name($id, $i)),
'type' => @mysql_field_type($id, $i),
'len' => @mysql_field_len($id, $i),
'flags' => @mysql_field_flags($id, $i),
);
if ($mode & DB_TABLEINFO_ORDER) {
$res['order'][$res[$i]['name']] = $i;
}
if ($mode & DB_TABLEINFO_ORDERTABLE) {
$res['ordertable'][$res[$i]['table']][$res[$i]['name']] = $i;
}
}
// free the result only if we were called on a table
if ($got_string) {
@mysql_free_result($id);
}
return $res;
}
// }}}
// {{{ getSpecialQuery()
/**
* Obtains the query string needed for listing a given type of objects
*
* @param string $type the kind of objects you want to retrieve
*
* @return string the SQL query string or null if the driver doesn't
* support the object type requested
*
* @access protected
* @see DB_common::getListOf()
*/
function getSpecialQuery($type)
{
switch ($type) {
case 'tables':
return 'SHOW TABLES';
case 'users':
return 'SELECT DISTINCT User FROM mysql.user';
case 'databases':
return 'SHOW DATABASES';
default:
return null;
}
}
// }}}
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
*/
?>
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