<?php
/**
* @package Joomla.Platform
* @subpackage Database
*
* @copyright Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
defined('JPATH_PLATFORM') or die;
/**
* Query Building Class.
*
* @since 1.7.0
*/
class JDatabaseQuerySqlsrv extends JDatabaseQuery implements JDatabaseQueryLimitable
{
/**
* The character(s) used to quote SQL statement names such as table names or field names,
* etc. The child classes should define this as necessary. If a single character string the
* same character is used for both sides of the quoted name, else the first character will be
* used for the opening quote and the second for the closing quote.
*
* @var string
* @since 1.7.0
*/
protected $name_quotes = '`';
/**
* The null or zero representation of a timestamp for the database driver. This should be
* defined in child classes to hold the appropriate value for the engine.
*
* @var string
* @since 1.7.0
*/
protected $null_date = '1900-01-01 00:00:00';
/**
* @var integer The affected row limit for the current SQL statement.
* @since 3.2
*/
protected $limit = 0;
/**
* @var integer The affected row offset to apply for the current SQL statement.
* @since 3.2
*/
protected $offset = 0;
/**
* Magic function to convert the query to a string.
*
* @return string The completed query.
*
* @since 1.7.0
*/
public function __toString()
{
$query = '';
switch ($this->type)
{
case 'select':
// Add required aliases for offset or fixGroupColumns method
$columns = $this->fixSelectAliases();
$query = (string) $this->select;
if ($this->group)
{
$this->fixGroupColumns($columns);
}
$query .= (string) $this->from;
if ($this->join)
{
// Special case for joins
foreach ($this->join as $join)
{
$query .= (string) $join;
}
}
if ($this->where)
{
$query .= (string) $this->where;
}
if ($this->selectRowNumber === null)
{
if ($this->group)
{
$query .= (string) $this->group;
}
if ($this->having)
{
$query .= (string) $this->having;
}
}
if ($this->order)
{
$query .= (string) $this->order;
}
if ($this instanceof JDatabaseQueryLimitable && ($this->limit > 0 || $this->offset > 0))
{
$query = $this->processLimit($query, $this->limit, $this->offset);
}
break;
case 'insert':
$query .= (string) $this->insert;
// Set method
if ($this->set)
{
$query .= (string) $this->set;
}
// Columns-Values method
elseif ($this->values)
{
if ($this->columns)
{
$query .= (string) $this->columns;
}
$elements = $this->insert->getElements();
$tableName = array_shift($elements);
$query .= 'VALUES ';
$query .= (string) $this->values;
if ($this->autoIncrementField)
{
$query = 'SET IDENTITY_INSERT ' . $tableName . ' ON;' . $query . 'SET IDENTITY_INSERT ' . $tableName . ' OFF;';
}
if ($this->where)
{
$query .= (string) $this->where;
}
}
break;
case 'delete':
$query .= (string) $this->delete;
$query .= (string) $this->from;
if ($this->join)
{
// Special case for joins
foreach ($this->join as $join)
{
$query .= (string) $join;
}
}
if ($this->where)
{
$query .= (string) $this->where;
}
if ($this->order)
{
$query .= (string) $this->order;
}
break;
case 'update':
if ($this->join)
{
$tmpUpdate = $this->update;
$tmpFrom = $this->from;
$this->update = null;
$this->from = null;
$updateElem = $tmpUpdate->getElements();
$updateArray = explode(' ', $updateElem[0]);
// Use table alias if exists
$this->update(end($updateArray));
$this->from($updateElem[0]);
$query .= (string) $this->update;
$query .= (string) $this->set;
$query .= (string) $this->from;
$this->update = $tmpUpdate;
$this->from = $tmpFrom;
// Special case for joins
foreach ($this->join as $join)
{
$query .= (string) $join;
}
}
else
{
$query .= (string) $this->update;
$query .= (string) $this->set;
}
if ($this->where)
{
$query .= (string) $this->where;
}
if ($this->order)
{
$query .= (string) $this->order;
}
break;
default:
$query = parent::__toString();
break;
}
return $query;
}
/**
* Casts a value to a char.
*
* Ensure that the value is properly quoted before passing to the method.
*
* @param string $value The value to cast as a char.
*
* @param string $len The lenght of the char.
*
* @return string Returns the cast value.
*
* @since 1.7.0
*/
public function castAsChar($value, $len = null)
{
if (!$len)
{
return 'CAST(' . $value . ' as NVARCHAR(30))';
}
else
{
return 'CAST(' . $value . ' as NVARCHAR(' . $len . '))';
}
}
/**
* Gets the function to determine the length of a character string.
*
* @param string $field A value.
* @param string $operator Comparison operator between charLength integer value and $condition
* @param string $condition Integer value to compare charLength with.
*
* @return string The required char length call.
*
* @since 1.7.0
*/
public function charLength($field, $operator = null, $condition = null)
{
return 'DATALENGTH(' . $field . ')' . (isset($operator) && isset($condition) ? ' ' . $operator . ' ' . $condition : '');
}
/**
* Concatenates an array of column names or values.
*
* @param array $values An array of values to concatenate.
* @param string $separator As separator to place between each value.
*
* @return string The concatenated values.
*
* @since 1.7.0
*/
public function concatenate($values, $separator = null)
{
if ($separator)
{
return '(' . implode('+' . $this->quote($separator) . '+', $values) . ')';
}
else
{
return '(' . implode('+', $values) . ')';
}
}
/**
* Gets the current date and time.
*
* @return string
*
* @since 1.7.0
*/
public function currentTimestamp()
{
return 'GETDATE()';
}
/**
* Get the length of a string in bytes.
*
* @param string $value The string to measure.
*
* @return integer
*
* @since 1.7.0
*/
public function length($value)
{
return 'LEN(' . $value . ')';
}
/**
* Add to the current date and time.
* Usage:
* $query->select($query->dateAdd());
* Prefixing the interval with a - (negative sign) will cause subtraction to be used.
*
* @param datetime $date The date to add to; type may be time or datetime.
* @param string $interval The string representation of the appropriate number of units
* @param string $datePart The part of the date to perform the addition on
*
* @return string The string with the appropriate sql for addition of dates
*
* @since 3.2.0
* @note Not all drivers support all units.
* @link http://msdn.microsoft.com/en-us/library/ms186819.aspx for more information
*/
public function dateAdd($date, $interval, $datePart)
{
return "DATEADD('" . $datePart . "', '" . $interval . "', '" . $date . "'" . ')';
}
/**
* Method to modify a query already in string format with the needed
* additions to make the query limited to a particular number of
* results, or start at a particular offset.
*
* @param string $query The query in string format
* @param integer $limit The limit for the result set
* @param integer $offset The offset for the result set
*
* @return string
*
* @since 3.0.0
*/
public function processLimit($query, $limit, $offset = 0)
{
if ($limit)
{
$total = $offset + $limit;
$position = stripos($query, 'SELECT');
$distinct = stripos($query, 'SELECT DISTINCT');
if ($position === $distinct)
{
$query = substr_replace($query, 'SELECT DISTINCT TOP ' . (int) $total, $position, 15);
}
else
{
$query = substr_replace($query, 'SELECT TOP ' . (int) $total, $position, 6);
}
}
if (!$offset)
{
return $query;
}
return PHP_EOL
. 'SELECT * FROM (SELECT *, ROW_NUMBER() OVER (ORDER BY (SELECT 0)) AS RowNumber FROM ('
. $query
. PHP_EOL . ') AS A) AS A WHERE RowNumber > ' . (int) $offset;
}
/**
* Sets the offset and limit for the result set, if the database driver supports it.
*
* Usage:
* $query->setLimit(100, 0); (retrieve 100 rows, starting at first record)
* $query->setLimit(50, 50); (retrieve 50 rows, starting at 50th record)
*
* @param integer $limit The limit for the result set
* @param integer $offset The offset for the result set
*
* @return JDatabaseQuery Returns this object to allow chaining.
*
* @since 3.0.0
*/
public function setLimit($limit = 0, $offset = 0)
{
$this->limit = (int) $limit;
$this->offset = (int) $offset;
return $this;
}
/**
* Split a string of sql expression into an array of individual columns.
* Single line or line end comments and multi line comments are stripped off.
* Always return at least one column.
*
* @param string $string Input string of sql expression like select expression.
*
* @return array[] The columns from the input string separated into an array.
*
* @since 3.7.0
*/
protected function splitSqlExpression($string)
{
// Append whitespace as equivalent to the last comma
$string .= ' ';
$colIdx = 0;
$start = 0;
$open = false;
$openC = 0;
$comment = false;
$endString = '';
$length = strlen($string);
$columns = array();
$column = array();
$current = '';
$previous = null;
$operators = array(
'+' => '',
'-' => '',
'*' => '',
'/' => '',
'%' => '',
'&' => '',
'|' => '',
'~' => '',
'^' => '',
);
$addBlock = function ($block) use (&$column, &$colIdx)
{
if (isset($column[$colIdx]))
{
$column[$colIdx] .= $block;
}
else
{
$column[$colIdx] = $block;
}
};
for ($i = 0; $i < $length; $i++)
{
$current = substr($string, $i, 1);
$current2 = substr($string, $i, 2);
$current3 = substr($string, $i, 3);
$lenEndString = strlen($endString);
$testEnd = substr($string, $i, $lenEndString);
if ($current == '[' || $current == '"' || $current == "'" || $current2 == '--'
|| ($current2 == '/*') || ($current == '#' && $current3 != '#__')
|| ($lenEndString && $testEnd == $endString))
{
if ($open)
{
if ($testEnd === $endString)
{
if ($comment)
{
if ($lenEndString > 1)
{
$i += ($lenEndString - 1);
}
// Move cursor after close tag of comment
$start = $i + 1;
$comment = false;
}
elseif ($current == "'" || $current == ']' || $current == '"')
{
// Check for escaped quote like '', ]] or ""
$n = 1;
while ($i + $n < $length && $string[$i + $n] == $current)
{
$n++;
}
// Jump to the last quote
$i += $n - 1;
if ($n % 2 === 0)
{
// There is only escaped quote
continue;
}
elseif ($n > 2)
{
// The last right close quote is not escaped
$current = $string[$i];
}
}
$open = false;
$endString = '';
}
}
else
{
$open = true;
if ($current == '#' || $current2 == '--')
{
$endString = "\n";
$comment = true;
}
elseif ($current2 == '/*')
{
$endString = '*/';
$comment = true;
}
elseif ($current == '[')
{
$endString = ']';
}
else
{
$endString = $current;
}
if ($comment && $start < $i)
{
// Add string exists before comment
$addBlock(substr($string, $start, $i - $start));
$previous = $string[$i - 1];
$start = $i;
}
}
}
elseif (!$open)
{
if ($current == '(')
{
$openC++;
$previous = $current;
}
elseif ($current == ')')
{
$openC--;
$previous = $current;
}
elseif ($current == '.')
{
if ($i === $start && $colIdx > 0 && !isset($column[$colIdx]))
{
// Remove whitepace placed before dot
$colIdx--;
}
$previous = $current;
}
elseif ($openC === 0)
{
if (ctype_space($current))
{
// Normalize whitepace
$string[$i] = ' ';
if ($start < $i)
{
// Add text placed before whitespace
$addBlock(substr($string, $start, $i - $start));
$colIdx++;
$previous = $string[$i - 1];
}
elseif (isset($column[$colIdx]))
{
if ($colIdx > 1 || !isset($operators[$previous]))
{
// There was whitespace after comment
$colIdx++;
}
}
// Move cursor forward
$start = $i + 1;
}
elseif (isset($operators[$current]) && ($current !== '*' || $previous !== '.'))
{
if ($start < $i)
{
// Add text before operator
$addBlock(substr($string, $start, $i - $start));
$colIdx++;
}
elseif (!isset($column[$colIdx]) && isset($operators[$previous]))
{
// Do not create whitespace between operators
$colIdx--;
}
// Add operator
$addBlock($current);
$previous = $current;
$colIdx++;
// Move cursor forward
$start = $i + 1;
}
else
{
$previous = $current;
}
}
}
if (($current == ',' && !$open && $openC == 0) || $i == $length - 1)
{
if ($start < $i && !$comment)
{
// Save remaining text
$addBlock(substr($string, $start, $i - $start));
}
$columns[] = $column;
// Reset values
$column = array();
$colIdx = 0;
$previous = null;
// Column saved, move cursor forward after comma
$start = $i + 1;
}
}
return $columns;
}
/**
* Add required aliases to columns for select statement in subquery.
*
* @return array[] Array of columns with added missing aliases.
*
* @since 3.7.0
*/
protected function fixSelectAliases()
{
$operators = array(
'+' => '',
'-' => '',
'*' => '',
'/' => '',
'%' => '',
'&' => '',
'|' => '',
'~' => '',
'^' => '',
);
// Split into array and remove comments
$columns = $this->splitSqlExpression(implode(',', $this->select->getElements()));
foreach ($columns as $i => $column)
{
$size = count($column);
if ($size == 0)
{
continue;
}
if ($size > 2 && strcasecmp($column[$size - 2], 'AS') === 0)
{
// Alias exists, replace it to uppercase
$columns[$i][$size - 2] = 'AS';
continue;
}
if ($i == 0 && stripos(' DISTINCT ALL ', " $column[0] ") !== false)
{
// This words are reserved, they are not column names
array_shift($column);
$size--;
}
$lastWord = strtoupper($column[$size - 1]);
$length = strlen($lastWord);
$lastChar = $lastWord[$length - 1];
if ($lastChar == '*')
{
// Skip on wildcard
continue;
}
if ($lastChar == ')'
|| ($size == 1 && $lastChar == "'")
|| $lastWord[0] == '@'
|| $lastWord == 'NULL'
|| $lastWord == 'END'
|| is_numeric($lastWord))
{
/* Ends with:
* - SQL function
* - single static value like 'only '+'string'
* - @@var
* - NULL
* - CASE ... END
* - Numeric
*/
$columns[$i][] = 'AS';
$columns[$i][] = $this->quoteName('columnAlias' . $i);
continue;
}
if ($size == 1)
{
continue;
}
$lastChar2 = substr($column[$size - 2], -1);
// Check if column ends with '- a.x' or '- a. x'
if (isset($operators[$lastChar2])
|| ($size > 2 && $lastChar2 === '.' && isset($operators[substr($column[$size - 3], -1)])))
{
// Ignore plus signs if column start with them
if ($size != 2 || ltrim($column[0], '+') !== '' || $column[1][0] === "'")
{
// If operator exists before last word then alias is required for subquery
$columns[$i][] = 'AS';
$columns[$i][] = $this->quoteName('columnAlias' . $i);
continue;
}
}
elseif ($column[$size - 1][0] !== '.' && $lastChar2 !== '.')
{
// If columns is like name name2 then second word is alias.
// Add missing AS before the alias, exception for 'a. x' and 'a .x'
array_splice($columns[$i], -1, 0, 'AS');
}
}
$selectColumns = array();
foreach ($columns as $i => $column)
{
$selectColumns[$i] = implode(' ', $column);
}
$this->select = new JDatabaseQueryElement('SELECT', $selectColumns);
return $columns;
}
/**
* Add missing columns names to GROUP BY clause.
*
* @param array[] $selectColumns Array of columns from splitSqlExpression method.
*
* @return JDatabaseQuery Returns this object to allow chaining.
*
* @since 3.7.0
*/
protected function fixGroupColumns($selectColumns)
{
// Cache tables columns
static $cacheCols = array();
// Known columns of all included tables
$knownColumnsByAlias = array();
$iquotes = array('"' => '', '[' => '', "'" => '');
$nquotes = array('"', '[', ']');
// Aggregate functions
$aFuncs = array(
'AVG(',
'CHECKSUM_AGG(',
'COUNT(',
'COUNT_BIG(',
'GROUPING(',
'GROUPING_ID(',
'MIN(',
'MAX(',
'SUM(',
'STDEV(',
'STDEVP(',
'VAR(',
'VARP(',
);
// Aggregated columns
$filteredColumns = array();
// Aliases found in SELECT statement
$knownAliases = array();
$wildcardTables = array();
foreach ($selectColumns as $i => $column)
{
$size = count($column);
if ($size === 0)
{
continue;
}
if ($size > 2 && $column[$size - 2] === 'AS')
{
// Save and remove AS alias
$alias = $column[$size - 1];
if (isset($iquotes[$alias[0]]))
{
$alias = substr($alias, 1, -1);
}
// Remove alias
$selectColumns[$i] = $column = array_slice($column, 0, -2);
if ($size === 3 || ($size === 4 && strpos('+-*/%&|~^', $column[0][0]) !== false))
{
$lastWord = $column[$size - 3];
if ($lastWord[0] === "'" || $lastWord === 'NULL' || is_numeric($lastWord))
{
unset($selectColumns[$i]);
continue;
}
}
// Remember pair alias => column expression
$knownAliases[$alias] = implode(' ', $column);
}
$aggregated = false;
foreach ($column as $j => $block)
{
if (substr($block, -2) === '.*')
{
// Found column ends with .*
if (isset($iquotes[$block[0]]))
{
// Quoted table
$wildcardTables[] = substr($block, 1, -3);
}
else
{
$wildcardTables[] = substr($block, 0, -2);
}
}
elseif (str_ireplace($aFuncs, '', $block) != $block)
{
$aggregated = true;
}
if ($block[0] === "'")
{
// Shrink static strings which could contain column name
$column[$j] = "''";
}
}
if (!$aggregated)
{
// Without aggregated columns and aliases
$filteredColumns[] = implode(' ', $selectColumns[$i]);
}
// Without aliases and static strings
$selectColumns[$i] = implode(' ', $column);
}
// If select statement use table.* expression
if ($wildcardTables)
{
// Split FROM statement into list of tables
$tables = $this->splitSqlExpression(implode(',', $this->from->getElements()));
foreach ($tables as $i => $table)
{
$table = implode(' ', $table);
// Exclude subquery from the FROM clause
if (strpos($table, '(') === false)
{
// Unquote
$table = str_replace($nquotes, '', $table);
$table = str_replace('#__', $this->db->getPrefix(), $table);
$table = explode(' ', $table);
$alias = end($table);
$table = $table[0];
// Chek if exists a wildcard with current alias table?
if (in_array($alias, $wildcardTables, true))
{
if (!isset($cacheCols[$table]))
{
$cacheCols[$table] = $this->db->getTableColumns($table);
}
if ($this->join || $table != $alias)
{
foreach ($cacheCols[$table] as $name => $type)
{
$knownColumnsByAlias[$alias][] = $alias . '.' . $name;
}
}
else
{
foreach ($cacheCols[$table] as $name => $type)
{
$knownColumnsByAlias[$alias][] = $name;
}
}
}
}
}
// Now we need to get all tables from any joins
// Go through all joins and add them to the tables array
if ($this->join)
{
foreach ($this->join as $join)
{
// Unquote and replace prefix
$joinTbl = str_replace($nquotes, '', (string) $join);
$joinTbl = str_replace("#__", $this->db->getPrefix(), $joinTbl);
// Exclude subquery
if (preg_match('/JOIN\s+(\w+)(?:\s+AS)?(?:\s+(\w+))?/i', $joinTbl, $matches))
{
$table = $matches[1];
$alias = isset($matches[2]) ? $matches[2] : $table;
// Chek if exists a wildcard with current alias table?
if (in_array($alias, $wildcardTables, true))
{
if (!isset($cacheCols[$table]))
{
$cacheCols[$table] = $this->db->getTableColumns($table);
}
foreach ($cacheCols[$table] as $name => $type)
{
$knownColumnsByAlias[$alias][] = $alias . '.' . $name;
}
}
}
}
}
}
$selectExpression = implode(',', $selectColumns);
// Split into the right columns
$groupColumns = $this->splitSqlExpression(implode(',', $this->group->getElements()));
// Remove column aliases from GROUP statement - SQLSRV does not support it
foreach ($groupColumns as $i => $column)
{
$groupColumns[$i] = implode(' ', $column);
$column = str_replace($nquotes, '', $groupColumns[$i]);
if (isset($knownAliases[$column]))
{
// Be sure that this is not a valid column name
if (!preg_match('/\b' . preg_quote($column, '/') . '\b/', $selectExpression))
{
// Replace column alias by column expression
$groupColumns[$i] = $knownAliases[$column];
}
}
}
// Find all alias.* and fill with proper table column names
foreach ($filteredColumns as $i => $column)
{
if (substr($column, -2) === '.*')
{
unset($filteredColumns[$i]);
// Extract alias.* columns into GROUP BY statement
$groupColumns = array_merge($groupColumns, $knownColumnsByAlias[substr($column, 0, -2)]);
}
}
$groupColumns = array_merge($groupColumns, $filteredColumns);
if ($this->order)
{
// Remove direction suffixes
$dir = array(" DESC\v", " ASC\v");
$orderColumns = $this->splitSqlExpression(implode(',', $this->order->getElements()));
foreach ($orderColumns as $i => $column)
{
$column = implode(' ', $column);
$orderColumns[$i] = $column = trim(str_ireplace($dir, '', "$column\v"), "\v");
if (isset($knownAliases[str_replace($nquotes, '', $column)]))
{
unset($orderColumns[$i]);
}
if (str_ireplace($aFuncs, '', $column) != $column)
{
// Do not add aggregate expression
unset($orderColumns[$i]);
}
}
$groupColumns = array_merge($groupColumns, $orderColumns);
}
// Get a unique string of all column names that need to be included in the group statement
$this->group = new JDatabaseQueryElement('GROUP BY', array_unique($groupColumns));
return $this;
}
/**
* Return correct rand() function for MSSQL.
*
* Ensure that the rand() function is MSSQL compatible.
*
* Usage:
* $query->Rand();
*
* @return string The correct rand function.
*
* @since 3.5
*/
public function Rand()
{
return ' NEWID() ';
}
}