<?php
/**
* MyBB 1.6
* Copyright 2010 MyBB Group, All Rights Reserved
*
* Website: http://www.mybboard.com
* License: http://www.mybboard.com/license.php
*
* $Id: db_sqlite.php 5828 2012-05-08 16:06:16Z Tomm $
*/
class DB_SQLite
{
/**
* The title of this layer.
*
* @var string
*/
public $title = "SQLite 3";
/**
* The short title of this layer.
*
* @var string
*/
public $short_title = "SQLite";
/**
* The type of db software being used.
*
* @var string
*/
public $type;
/**
* A count of the number of queries.
*
* @var int
*/
public $query_count = 0;
/**
* A list of the performed queries.
*
* @var array
*/
public $querylist = array();
/**
* 1 if error reporting enabled, 0 if disabled.
*
* @var boolean
*/
public $error_reporting = 1;
/**
* The database connection resource.
*
* @var resource
*/
public $link;
/**
* Explanation of a query.
*
* @var string
*/
public $explain;
/**
* The current version of SQLite.
*
* @var string
*/
public $version;
/**
* The current table type in use (myisam/innodb)
*
* @var string
*/
public $table_type = "myisam";
/**
* The table prefix used for simple select, update, insert and delete queries
*
* @var string
*/
public $table_prefix;
/**
* The extension used to run the SQL database
*
* @var string
*/
public $engine = "pdo";
/**
* Weather or not this engine can use the search functionality
*
* @var boolean
*/
public $can_search = true;
/**
* The database encoding currently in use (if supported)
*
* @var string
*/
public $db_encoding = "";
/**
* The time spent performing queries
*
* @var float
*/
public $query_time = 0;
/**
* Connect to the database server.
*
* @param array Array of DBMS connection details.
* @return resource The DB connection resource. Returns false on failure.
*/
function connect($config)
{
$this->get_execution_time();
require_once MYBB_ROOT."inc/db_pdo.php";
$this->db = new dbpdoEngine("sqlite:{$config['database']}");
$query_time = $this->get_execution_time();
$this->query_time += $query_time;
$this->connections[] = "[WRITE] {$config['database']} (Connected in ".number_format($query_time, 0)."s)";
if($this->db)
{
$this->query('PRAGMA short_column_names = 1');
return true;
}
else
{
return false;
}
}
/**
* Query the database.
*
* @param string The query SQL.
* @param boolean 1 if hide errors, 0 if not.
* @return resource The query data.
*/
function query($string, $hide_errors=0)
{
global $pagestarttime, $db, $mybb;
$this->get_execution_time();
if(strtolower(substr(ltrim($string), 0, 5)) == 'alter')
{
$string = preg_replace("#\sAFTER\s([a-z_]+?)(;*?)$#i", "", $string);
$queryparts = preg_split("/[\s]+/", $string, 4, PREG_SPLIT_NO_EMPTY);
$tablename = $queryparts[2];
$alterdefs = $queryparts[3];
if(strtolower($queryparts[1]) != 'table' || $queryparts[2] == '')
{
$this->error_msg = "near \"{$queryparts[0]}\": syntax error";
}
else
{
// SQLITE 3 supports ADD Alter statements
if(strtolower(substr(ltrim($string), 0, 3)) == 'add')
{
$query = $this->db->query($string);
}
else
{
$query = $this->alter_table_parse($tablename, $alterdefs, $string);
}
}
}
else
{
try
{
$query = $this->db->query($string);
}
catch(PDOException $exception)
{
$error = array(
"message" => $exception->getMessage(),
"code" => $exception->getCode()
);
$this->error($error['message'], $error['code']);
}
}
if($this->error_number($query) > 0 && !$hide_errors)
{
$this->error($string, $query);
exit;
}
$query_time = $this->get_execution_time();
$this->query_time += $query_time;
$this->query_count++;
if($mybb->debug_mode)
{
$this->explain_query($string, $query_time);
}
return $query;
}
/**
* Explain a query on the database.
*
* @param string The query SQL.
* @param string The time it took to perform the query.
*/
function explain_query($string, $qtime)
{
if(preg_match("#^\s*select#i", $string))
{
$this->explain .= "<table style=\"background-color: #666;\" width=\"95%\" cellpadding=\"4\" cellspacing=\"1\" align=\"center\">\n".
"<tr>\n".
"<td colspan=\"8\" style=\"background-color: #ccc;\"><strong>#".$this->query_count." - Select Query</strong></td>\n".
"</tr>\n".
"<tr>\n".
"<td colspan=\"8\" style=\"background-color: #fefefe;\"><span style=\"font-family: Courier; font-size: 14px;\">".$string."</span></td>\n".
"</tr>\n".
"<tr>\n".
"<td colspan=\"8\" style=\"background-color: #fff;\">Query Time: ".$qtime."</td>\n".
"</tr>\n".
"</table>\n".
"<br />\n";
}
else
{
$this->explain .= "<table style=\"background-color: #666;\" width=\"95%\" cellpadding=\"4\" cellspacing=\"1\" align=\"center\">\n".
"<tr>\n".
"<td style=\"background-color: #ccc;\"><strong>#".$this->query_count." - Write Query</strong></td>\n".
"</tr>\n".
"<tr style=\"background-color: #fefefe;\">\n".
"<td><span style=\"font-family: Courier; font-size: 14px;\">".htmlspecialchars_uni($string)."</span></td>\n".
"</tr>\n".
"<tr>\n".
"<td bgcolor=\"#ffffff\">Query Time: ".$qtime."</td>\n".
"</tr>\n".
"</table>\n".
"<br />\n";
}
$this->querylist[$this->query_count]['query'] = $string;
$this->querylist[$this->query_count]['time'] = $qtime;
}
/**
* Execute a write query on the database
*
* @param string The query SQL.
* @param boolean 1 if hide errors, 0 if not.
* @return resource The query data.
*/
function write_query($query, $hide_errors=0)
{
return $this->query($query, $hide_errors);
}
/**
* Return a result array for a query.
*
* @param resource The result data.
* @param constant The type of array to return.
* @return array The array of results.
*/
function fetch_array($query)
{
$array = $this->db->fetch_array($query);
return $array;
}
/**
* Return a specific field from a query.
*
* @param resource The query ID.
* @param string The name of the field to return.
* @param int The number of the row to fetch it from.
*/
function fetch_field($query, $field, $row=false)
{
if($row !== false)
{
$this->data_seek($query, $row);
}
$array = $this->fetch_array($query);
return $array[$field];
}
/**
* Moves internal row pointer to the next row
*
* @param resource The query ID.
* @param int The pointer to move the row to.
*/
function data_seek($query, $row)
{
return $this->db->seek($query, $row);
}
/**
* Return the number of rows resulting from a query.
*
* @param resource The query data.
* @return int The number of rows in the result.
*/
function num_rows($query)
{
return $this->db->num_rows($query);
}
/**
* Return the last id number of inserted data.
*
* @return int The id number.
*/
function insert_id($name="")
{
return $this->db->insert_id($name);
}
/**
* Close the connection with the DBMS.
*
*/
function close()
{
return;
}
/**
* Return an error number.
*
* @return int The error number of the current error.
*/
function error_number($query="")
{
if(!$query)
{
$query = $this->db->last_query;
}
$this->error_number = $this->db->error_number($query);
return $this->error_number;
}
/**
* Return an error string.
*
* @return string The explanation for the current error.
*/
function error_string($query="")
{
if($this->error_number != "")
{
if(!$query)
{
$query = $this->db->last_query;
}
$error_string = $this->db->error_string($query);
$this->error_number = "";
return $error_string;
}
}
/**
* Output a database error.
*
* @param string The string to present as an error.
*/
function error($string="", $query="", $error="", $error_no="")
{
$this->db->roll_back();
if($this->error_reporting)
{
if(!$query)
{
$query = $this->db->last_query;
}
if($error_no == "")
{
$error_no = $this->error_number($query);
}
if($error == "")
{
$error = $this->error_string($query);
}
if(class_exists("errorHandler"))
{
global $error_handler;
if(!is_object($error_handler))
{
require_once MYBB_ROOT."inc/class_error.php";
$error_handler = new errorHandler();
}
$error = array(
"error_no" => $error_no,
"error" => $error,
"query" => $string
);
$error_handler->error(MYBB_SQL, $error);
}
else
{
trigger_error("<strong>[SQL] [{$error_no}] {$error}</strong><br />{$string}", E_USER_ERROR);
}
}
}
/**
* Returns the number of affected rows in a query.
*
* @return int The number of affected rows.
*/
function affected_rows($query="")
{
if(!$query)
{
$query = $this->db->last_query;
}
return $this->db->affected_rows($query);
}
/**
* Return the number of fields.
*
* @param resource The query data.
* @return int The number of fields.
*/
function num_fields($query)
{
if(!$query)
{
$query = $this->db->last_query;
}
return $this->db->num_fields($query);
}
/**
* Lists all functions in the database.
*
* @param string The database name.
* @param string Prefix of the table (optional)
* @return array The table list.
*/
function list_tables($database, $prefix='')
{
if($prefix)
{
$query = $this->query("SELECT tbl_name FROM sqlite_master WHERE type = 'table' AND tbl_name LIKE '".$this->escape_string($prefix)."%'");
}
else
{
$query = $this->query("SELECT tbl_name FROM sqlite_master WHERE type = 'table'");
}
while($table = $this->fetch_array($query))
{
$tables[] = $table['tbl_name'];
}
return $tables;
}
/**
* Check if a table exists in a database.
*
* @param string The table name.
* @return boolean True when exists, false if not.
*/
function table_exists($table)
{
$query = $this->query("SELECT COUNT(name) as count FROM sqlite_master WHERE type='table' AND name='{$this->table_prefix}{$table}'");
$exists = $this->fetch_field($query, "count");
if($exists > 0)
{
return true;
}
else
{
return false;
}
}
/**
* Check if a field exists in a database.
*
* @param string The field name.
* @param string The table name.
* @return boolean True when exists, false if not.
*/
function field_exists($field, $table)
{
$query = $this->query("PRAGMA table_info('{$this->table_prefix}{$table}')");
$exists = 0;
while($row = $this->fetch_array($query))
{
if($row['name'] == $field)
{
++$exists;
}
}
if($exists > 0)
{
return true;
}
else
{
return false;
}
}
/**
* Add a shutdown query.
*
* @param resource The query data.
* @param string An optional name for the query.
*/
function shutdown_query($query, $name=0)
{
global $shutdown_queries;
if($name)
{
$shutdown_queries[$name] = $query;
}
else
{
$shutdown_queries[] = $query;
}
}
/**
* Performs a simple select query.
*
* @param string The table name to be queried.
* @param string Comma delimetered list of fields to be selected.
* @param string SQL formatted list of conditions to be matched.
* @param array List of options, order by, order direction, limit, limit start
*/
function simple_select($table, $fields="*", $conditions="", $options=array())
{
$query = "SELECT ".$fields." FROM ".$this->table_prefix.$table;
if($conditions != "")
{
$query .= " WHERE ".$conditions;
}
if(isset($options['order_by']))
{
$query .= " ORDER BY ".$options['order_by'];
if(isset($options['order_dir']))
{
$query .= " ".strtoupper($options['order_dir']);
}
}
if(isset($options['limit_start']) && isset($options['limit']))
{
$query .= " LIMIT ".$options['limit_start'].", ".$options['limit'];
}
else if(isset($options['limit']))
{
$query .= " LIMIT ".$options['limit'];
}
return $this->query($query);
}
/**
* Build an insert query from an array.
*
* @param string The table name to perform the query on.
* @param array An array of fields and their values.
* @return int The insert ID if available
*/
function insert_query($table, $array)
{
if(!is_array($array))
{
return false;
}
$fields = implode(",", array_keys($array));
$values = implode("','", $array);
$this->write_query("
INSERT
INTO {$this->table_prefix}{$table} (".$fields.")
VALUES ('".$values."')
");
return $this->insert_id();
}
/**
* Build one query for multiple inserts from a multidimensional array.
*
* @param string The table name to perform the query on.
* @param array An array of inserts.
* @return int The insert ID if available
*/
function insert_query_multiple($table, $array)
{
if(!is_array($array))
{
return false;
}
// Field names
$fields = array_keys($array[0]);
$fields = implode(",", $fields);
$insert_rows = array();
foreach($array as $values)
{
$insert_rows[] = "('".implode("','", $values)."')";
}
$insert_rows = implode(", ", $insert_rows);
$this->write_query("
INSERT
INTO {$this->table_prefix}{$table} ({$fields})
VALUES {$insert_rows}
");
}
/**
* Build an update query from an array.
*
* @param string The table name to perform the query on.
* @param array An array of fields and their values.
* @param string An optional where clause for the query.
* @param string An optional limit clause for the query.
* @param boolean An option to quote incoming values of the array.
* @return resource The query data.
*/
function update_query($table, $array, $where="", $limit="", $no_quote=false)
{
if(!is_array($array))
{
return false;
}
$comma = "";
$query = "";
$quote = "'";
if($no_quote == true)
{
$quote = "";
}
foreach($array as $field => $value)
{
$query .= $comma.$field."={$quote}".$value."{$quote}";
$comma = ', ';
}
if(!empty($where))
{
$query .= " WHERE $where";
}
return $this->query("UPDATE {$this->table_prefix}$table SET $query");
}
/**
* Build a delete query.
*
* @param string The table name to perform the query on.
* @param string An optional where clause for the query.
* @param string An optional limit clause for the query.
* @return resource The query data.
*/
function delete_query($table, $where="", $limit="")
{
$query = "";
if(!empty($where))
{
$query .= " WHERE $where";
}
return $this->query("DELETE FROM {$this->table_prefix}$table $query");
}
/**
* Escape a string
*
* @param string The string to be escaped.
* @return string The escaped string.
*/
function escape_string($string)
{
$string = $this->db->escape_string($string);
return $string;
}
/**
* Serves no purposes except compatibility
*
*/
function free_result($query)
{
return;
}
/**
* Escape a string used within a like command.
*
* @param string The string to be escaped.
* @return string The escaped string.
*/
function escape_string_like($string)
{
return $this->escape_string(str_replace(array('%', '_') , array('\\%' , '\\_') , $string));
}
/**
* Gets the current version of SQLLite.
*
* @return string Version of MySQL.
*/
function get_version()
{
if($this->version)
{
return $this->version;
}
$this->version = $this->db->get_attribute("ATTR_SERVER_VERSION");
return $this->version;
}
/**
* Optimizes a specific table.
*
* @param string The name of the table to be optimized.
*/
function optimize_table($table)
{
$this->query("VACUUM ".$this->table_prefix.$table."");
}
/**
* Analyzes a specific table.
*
* @param string The name of the table to be analyzed.
*/
function analyze_table($table)
{
$this->query("ANALYZE ".$this->table_prefix.$table."");
}
/**
* Show the "create table" command for a specific table.
*
* @param string The name of the table.
* @return string The MySQL command to create the specified table.
*/
function show_create_table($table)
{
$old_tbl_prefix = $this->table_prefix;
$this->set_table_prefix("");
$query = $this->simple_select("sqlite_master", "sql", "type = 'table' AND name = '{$this->table_prefix}{$table}' ORDER BY type DESC, name");
$this->set_table_prefix($old_tbl_prefix);
return $this->fetch_field($query, 'sql');
}
/**
* Show the "show fields from" command for a specific table.
*
* @param string The name of the table.
* @return string Field info for that table
*/
function show_fields_from($table)
{
$old_tbl_prefix = $this->table_prefix;
$this->set_table_prefix("");
$query = $this->simple_select("sqlite_master", "sql", "type = 'table' AND name = '{$old_tbl_prefix}{$table}'");
$this->set_table_prefix($old_tbl_prefix);
$table = trim(preg_replace('#CREATE\s+TABLE\s+"?'.$this->table_prefix.$table.'"?#i', '', $this->fetch_field($query, "sql")));
preg_match('#\((.*)\)#s', $table, $matches);
$field_info = array();
$table_cols = explode(',', trim($matches[1]));
foreach($table_cols as $declaration)
{
$entities = preg_split('#\s+#', trim($declaration));
$column_name = preg_replace('/"?([^"]+)"?/', '\1', $entities[0]);
$field_info[] = array('Extra' => $entities[1], 'Field' => $column_name);
}
return $field_info;
}
/**
* Returns whether or not the table contains a fulltext index.
*
* @param string The name of the table.
* @param string Optionally specify the name of the index.
* @return boolean True or false if the table has a fulltext index or not.
*/
function is_fulltext($table, $index="")
{
return false;
}
/**
* Returns whether or not this database engine supports fulltext indexing.
*
* @param string The table to be checked.
* @return boolean True or false if supported or not.
*/
function supports_fulltext($table)
{
return false;
}
/**
* Returns whether or not this database engine supports boolean fulltext matching.
*
* @param string The table to be checked.
* @return boolean True or false if supported or not.
*/
function supports_fulltext_boolean($table)
{
return false;
}
/**
* Creates a fulltext index on the specified column in the specified table with optional index name.
*
* @param string The name of the table.
* @param string Name of the column to be indexed.
* @param string The index name, optional.
*/
function create_fulltext_index($table, $column, $name="")
{
return false;
}
/**
* Drop an index with the specified name from the specified table
*
* @param string The name of the table.
* @param string The name of the index.
*/
function drop_index($table, $name)
{
$this->query("ALTER TABLE {$this->table_prefix}$table DROP INDEX $name");
}
/**
* Checks to see if an index exists on a specified table
*
* @param string The name of the table.
* @param string The name of the index.
*/
function index_exists($table, $index)
{
return false;
}
/**
* Drop an table with the specified table
*
* @param string The name of the table.
* @param boolean hard drop - no checking
* @param boolean use table prefix
*/
function drop_table($table, $hard=false, $table_prefix=true)
{
if($table_prefix == false)
{
$table_prefix = "";
}
else
{
$table_prefix = $this->table_prefix;
}
if($hard == false)
{
if($this->table_exists($table))
{
$this->query('DROP TABLE '.$table_prefix.$table);
}
}
else
{
$this->query('DROP TABLE '.$table_prefix.$table);
}
}
/**
* Replace contents of table with values
*
* @param string The table
* @param array The replacements
* @param mixed The default field(s)
* @param boolean Whether or not to return an insert id. True by default
*/
function replace_query($table, $replacements=array(), $default_field="", $insert_id=true)
{
$columns = '';
$values = '';
$comma = '';
foreach($replacements as $column => $value)
{
$columns .= $comma.$column;
$values .= $comma."'".$value."'";
$comma = ',';
}
if(empty($columns) || empty($values))
{
return false;
}
if($default_field == "")
{
return $this->query("REPLACE INTO {$this->table_prefix}{$table} ({$columns}) VALUES({$values})");
}
else
{
$update = false;
if(is_array($default_field) && !empty($default_field))
{
$search_bit = array();
foreach($default_field as $field)
{
$search_bit[] = "{$field} = '".$replacements[$field]."'";
}
$search_bit = implode(" AND ", $search_bit);
$query = $this->write_query("SELECT COUNT(".$default_field[0].") as count FROM {$this->table_prefix}{$table} WHERE {$search_bit} LIMIT 1");
if($this->fetch_field($query, "count") == 1)
{
$update = true;
}
}
else
{
$query = $this->write_query("SELECT {$default_field} FROM {$this->table_prefix}{$table}");
while($column = $this->fetch_array($query))
{
if($column[$default_field] == $replacements[$default_field])
{
$update = true;
break;
}
}
}
if($update === true)
{
return $this->update_query($table, $replacements, $search_bit);
}
else
{
return $this->insert_query($table, $replacements, $insert_id);
}
}
}
/**
* Sets the table prefix used by the simple select, insert, update and delete functions
*
* @param string The new table prefix
*/
function set_table_prefix($prefix)
{
$this->table_prefix = $prefix;
}
/**
* Fetched the total size of all mysql tables or a specific table
*
* @param string The table (optional) (ignored)
* @return integer the total size of all mysql tables or a specific table
*/
function fetch_size($table='')
{
global $config, $lang;
$total = @filesize($config['database']['database']);
if(!$total || $table != '')
{
$total = $lang->na;
}
return $total;
}
/**
* Perform an "Alter Table" query in SQLite < 3.2.0 - Code taken from http://code.jenseng.com/db/
*
* @param string The table (optional)
* @return integer the total size of all mysql tables or a specific table
*/
function alter_table_parse($table, $alterdefs, $fullquery="")
{
if(!$fullquery)
{
$fullquery = " ... {$alterdefs}";
}
if(!defined("TIME_NOW"))
{
define("TIME_NOW", time());
}
if($alterdefs != '')
{
$result = $this->query("SELECT sql,name,type FROM sqlite_master WHERE tbl_name = '{$table}' ORDER BY type DESC");
if($this->num_rows($result) > 0)
{
$row = $this->fetch_array($result); // Table sql
$tmpname = 't'.TIME_NOW;
$origsql = trim(preg_replace("/[\s]+/", " ", str_replace(",", ", ", preg_replace("/[\(]/","( ", $row['sql'], 1))));
$createtemptableSQL = 'CREATE TEMPORARY '.substr(trim(preg_replace("'".$table."'", $tmpname, $origsql, 1)), 6);
$createindexsql = array();
$i = 0;
$defs = preg_split("/[,]+/", $alterdefs, -1, PREG_SPLIT_NO_EMPTY);
$prevword = $table;
$oldcols = preg_split("/[,]+/", substr(trim($createtemptableSQL), strpos(trim($createtemptableSQL), '(')+1), -1, PREG_SPLIT_NO_EMPTY);
$newcols = array();
for($i = 0; $i < sizeof($oldcols); $i++)
{
$colparts = preg_split("/[\s]+/", $oldcols[$i], -1, PREG_SPLIT_NO_EMPTY);
$oldcols[$i] = $colparts[0];
$newcols[$colparts[0]] = $colparts[0];
}
$newcolumns = '';
$oldcolumns = '';
reset($newcols);
foreach($newcols as $key => $val)
{
$newcolumns .= ($newcolumns ? ', ' : '').$val;
$oldcolumns .= ($oldcolumns ? ', ' : '').$key;
}
$copytotempsql = 'INSERT INTO '.$tmpname.'('.$newcolumns.') SELECT '.$oldcolumns.' FROM '.$table;
$dropoldsql = 'DROP TABLE '.$table;
$createtesttableSQL = $createtemptableSQL;
foreach($defs as $def)
{
$defparts = preg_split("/[\s]+/", $def, -1, PREG_SPLIT_NO_EMPTY);
$action = strtolower($defparts[0]);
switch($action)
{
case 'change':
if(sizeof($defparts) <= 3)
{
$this->error($alterdefs, 'near "'.$defparts[0].($defparts[1] ? ' '.$defparts[1] : '').($defparts[2] ? ' '.$defparts[2] : '').'": syntax error', E_USER_WARNING);
return false;
}
if($severpos = strpos($createtesttableSQL, ' '.$defparts[1].' '))
{
if($newcols[$defparts[1]] != $defparts[1])
{
$this->error($alterdefs, 'unknown column "'.$defparts[1].'" in "'.$table.'"');
return false;
}
$newcols[$defparts[1]] = $defparts[2];
$nextcommapos = strpos($createtesttableSQL, ',', $severpos);
$insertval = '';
for($i = 2; $i < sizeof($defparts); $i++)
{
$insertval .= ' '.$defparts[$i];
}
if($nextcommapos)
{
$createtesttableSQL = substr($createtesttableSQL, 0, $severpos).$insertval.substr($createtesttableSQL, $nextcommapos);
}
else
{
$createtesttableSQL = substr($createtesttableSQL, 0, $severpos-(strpos($createtesttableSQL, ',') ? 0 : 1)).$insertval.')';
}
}
else
{
$this->error($fullquery, 'unknown column "'.$defparts[1].'" in "'.$table.'"', E_USER_WARNING);
return false;
}
break;
case 'drop':
if(sizeof($defparts) < 2)
{
$this->error($fullquery, 'near "'.$defparts[0].($defparts[1] ? ' '.$defparts[1] : '').'": syntax error');
return false;
}
if($severpos = strpos($createtesttableSQL, ' '.$defparts[1].' '))
{
$nextcommapos = strpos($createtesttableSQL, ',', $severpos);
if($nextcommapos)
{
$createtesttableSQL = substr($createtesttableSQL, 0, $severpos).substr($createtesttableSQL, $nextcommapos + 1);
}
else
{
$createtesttableSQL = substr($createtesttableSQL, 0, $severpos-(strpos($createtesttableSQL, ',') ? 0 : 1) - 1).')';
}
unset($newcols[$defparts[1]]);
}
else
{
$this->error($fullquery, 'unknown column "'.$defparts[1].'" in "'.$table.'"');
return false;
}
break;
default:
$this->error($fullquery, 'near "'.$prevword.'": syntax error');
return false;
}
$prevword = $defparts[sizeof($defparts)-1];
}
// This block of code generates a test table simply to verify that the columns specifed are valid in an sql statement
// This ensures that no reserved words are used as columns, for example
$this->query($createtesttableSQL);
$droptempsql = 'DROP TABLE '.$tmpname;
if($this->query($droptempsql, 0) === false)
{
return false;
}
// End block
$createnewtableSQL = 'CREATE '.substr(trim(preg_replace("'{$tmpname}'", $table, $createtesttableSQL, 1)), 17);
$newcolumns = '';
$oldcolumns = '';
reset($newcols);
foreach($newcols as $key => $val)
{
$newcolumns .= ($newcolumns ? ', ' : '').$val;
$oldcolumns .= ($oldcolumns ? ', ' : '').$key;
}
$copytonewsql = 'INSERT INTO '.$table.'('.$newcolumns.') SELECT '.$oldcolumns.' FROM '.$tmpname;
$this->query($createtemptableSQL); // Create temp table
$this->query($copytotempsql); // Copy to table
$this->query($dropoldsql); // Drop old table
$this->query($createnewtableSQL); // Recreate original table
$this->query($copytonewsql); // Copy back to original table
$this->query($droptempsql); // Drop temp table
}
else
{
$this->error($fullquery, 'no such table: '.$table);
return false;
}
return true;
}
}
/**
* Drops a column
*
* @param string The table
* @param string The column name
*/
function drop_column($table, $column)
{
return $this->write_query("ALTER TABLE {$this->table_prefix}{$table} DROP {$column}");
}
/**
* Adds a column
*
* @param string The table
* @param string The column name
* @param string the new column definition
*/
function add_column($table, $column, $definition)
{
return $this->write_query("ALTER TABLE {$this->table_prefix}{$table} ADD {$column} {$definition}");
}
/**
* Modifies a column
*
* @param string The table
* @param string The column name
* @param string the new column definition
*/
function modify_column($table, $column, $new_definition)
{
// Yes, $column is repeated twice for a reason. It simulates a rename sql query, which SQLite supports.
return $this->write_query("ALTER TABLE {$this->table_prefix}{$table} CHANGE {$column} {$column} {$new_definition}");
}
/**
* Renames a column
*
* @param string The table
* @param string The old column name
* @param string the new column name
* @param string the new column definition
*/
function rename_column($table, $old_column, $new_column, $new_definition)
{
return $this->write_query("ALTER TABLE {$this->table_prefix}{$table} CHANGE {$old_column} {$new_column} {$new_definition}");
}
/**
* Fetch a list of database character sets this DBMS supports
*
* @return array Array of supported character sets with array key being the name, array value being display name. False if unsupported
*/
function fetch_db_charsets()
{
return false;
}
/**
* Fetch a database collation for a particular database character set
*
* @param string The database character set
* @return string The matching database collation, false if unsupported
*/
function fetch_charset_collation($charset)
{
return false;
}
/**
* Fetch a character set/collation string for use with CREATE TABLE statements. Uses current DB encoding
*
* @return string The built string, empty if unsupported
*/
function build_create_table_collation()
{
return '';
}
/**
* Time how long it takes for a particular piece of code to run. Place calls above & below the block of code.
*
* @return float The time taken
*/
function get_execution_time()
{
static $time_start;
$time = microtime(true);
// Just starting timer, init and return
if(!$time_start)
{
$time_start = $time;
return;
}
// Timer has run, return execution time
else
{
$total = $time-$time_start;
if($total < 0) $total = 0;
$time_start = 0;
return $total;
}
}
}
?>