<?php
/**
* Part of the Joomla Framework Database Package
*
* @copyright Copyright (C) 2005 - 2021 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
namespace Joomla\Database\Query;
/**
* Trait for PostgreSQL Query Building.
*
* @since 2.0.0
*/
trait PostgresqlQueryBuilder
{
/**
* The FOR UPDATE element used in "FOR UPDATE" lock
*
* @var QueryElement
* @since 2.0.0
*/
protected $forUpdate;
/**
* The FOR SHARE element used in "FOR SHARE" lock
*
* @var QueryElement
* @since 2.0.0
*/
protected $forShare;
/**
* The NOWAIT element used in "FOR SHARE" and "FOR UPDATE" lock
*
* @var QueryElement
* @since 2.0.0
*/
protected $noWait;
/**
* The LIMIT element
*
* @var QueryElement
* @since 2.0.0
*/
protected $limit;
/**
* The OFFSET element
*
* @var QueryElement
* @since 2.0.0
*/
protected $offset;
/**
* The RETURNING element of INSERT INTO
*
* @var QueryElement
* @since 2.0.0
*/
protected $returning;
/**
* Magic function to convert the query to a string, only for PostgreSQL specific queries
*
* @return string The completed query.
*
* @since 2.0.0
*/
public function __toString()
{
$query = '';
switch ($this->type)
{
case 'select':
$query .= (string) $this->select;
$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)
{
if ($this->order)
{
$query .= (string) $this->order;
}
break;
}
if ($this->group)
{
$query .= (string) $this->group;
}
if ($this->having)
{
$query .= (string) $this->having;
}
if ($this->merge)
{
// Special case for merge
foreach ($this->merge as $element)
{
$query .= (string) $element;
}
}
if ($this->order)
{
$query .= (string) $this->order;
}
if ($this->forUpdate)
{
$query .= (string) $this->forUpdate;
}
else
{
if ($this->forShare)
{
$query .= (string) $this->forShare;
}
}
if ($this->noWait)
{
$query .= (string) $this->noWait;
}
$query = $this->processLimit($query, $this->limit, $this->offset);
break;
case 'update':
$query .= (string) $this->update;
$query .= (string) $this->set;
if ($this->join)
{
$tmpFrom = $this->from;
$tmpWhere = $this->where ? clone $this->where : null;
$this->from = null;
// Workaround for special case of JOIN with UPDATE
foreach ($this->join as $join)
{
$joinElem = $join->getElements();
$this->from($joinElem[0]);
if (isset($joinElem[1]))
{
$this->where($joinElem[1]);
}
}
$query .= (string) $this->from;
if ($this->where)
{
$query .= (string) $this->where;
}
$this->from = $tmpFrom;
$this->where = $tmpWhere;
}
elseif ($this->where)
{
$query .= (string) $this->where;
}
$query = $this->processLimit($query, $this->limit, $this->offset);
break;
case 'insert':
$query .= (string) $this->insert;
if ($this->values)
{
if ($this->columns)
{
$query .= (string) $this->columns;
}
$elements = $this->values->getElements();
if (!($elements[0] instanceof $this))
{
$query .= ' VALUES ';
}
$query .= (string) $this->values;
if ($this->returning)
{
$query .= (string) $this->returning;
}
}
$query = $this->processLimit($query, $this->limit, $this->offset);
break;
default:
$query = parent::__toString();
break;
}
if ($this->type === 'select' && $this->alias !== null)
{
$query = '(' . $query . ') AS ' . $this->alias;
}
return $query;
}
/**
* Clear data from the query or a specific clause of the query.
*
* @param string $clause Optionally, the name of the clause to clear, or nothing to clear the whole query.
*
* @return $this
*
* @since 2.0.0
*/
public function clear($clause = null)
{
switch ($clause)
{
case 'limit':
$this->limit = null;
break;
case 'offset':
$this->offset = null;
break;
case 'forUpdate':
$this->forUpdate = null;
break;
case 'forShare':
$this->forShare = null;
break;
case 'noWait':
$this->noWait = null;
break;
case 'returning':
$this->returning = null;
break;
case 'select':
case 'update':
case 'delete':
case 'insert':
case 'querySet':
case 'from':
case 'join':
case 'set':
case 'where':
case 'group':
case 'having':
case 'merge':
case 'order':
case 'columns':
case 'values':
parent::clear($clause);
break;
default:
$this->forUpdate = null;
$this->forShare = null;
$this->noWait = null;
$this->returning = null;
parent::clear($clause);
break;
}
return $this;
}
/**
* Casts a value to a char.
*
* Ensure that the value is properly quoted before passing to the method.
*
* Usage:
* $query->select($query->castAs('CHAR', 'a'));
*
* @param string $type The type of string to cast as.
* @param string $value The value to cast as a char.
* @param string $length The value to cast as a char.
*
* @return string SQL statement to cast the value as a char type.
*
* @since 1.0
*/
public function castAs(string $type, string $value, ?string $length = null)
{
switch (strtoupper($type))
{
case 'CHAR':
if (!$length)
{
return $value . '::text';
}
else
{
return 'CAST(' . $value . ' AS CHAR(' . $length . '))';
}
case 'INT':
return 'CAST(' . $value . ' AS INTEGER)';
}
return parent::castAs($type, $value, $length);
}
/**
* Concatenates an array of column names or values.
*
* Usage:
* $query->select($query->concatenate(array('a', 'b')));
*
* @param string[] $values An array of values to concatenate.
* @param string|null $separator As separator to place between each value.
*
* @return string The concatenated values.
*
* @since 2.0.0
*/
public function concatenate($values, $separator = null)
{
if ($separator !== null)
{
return implode(' || ' . $this->quote($separator) . ' || ', $values);
}
return implode(' || ', $values);
}
/**
* Gets the current date and time.
*
* @return string Return string used in query to obtain
*
* @since 2.0.0
*/
public function currentTimestamp()
{
return 'NOW()';
}
/**
* Sets the FOR UPDATE lock on select's output row
*
* @param string $tableName The table to lock
* @param string $glue The glue by which to join the conditions. Defaults to ',' .
*
* @return $this
*
* @since 2.0.0
*/
public function forUpdate($tableName, $glue = ',')
{
$this->type = 'forUpdate';
if ($this->forUpdate === null)
{
$glue = strtoupper($glue);
$this->forUpdate = new QueryElement('FOR UPDATE', 'OF ' . $tableName, "$glue ");
}
else
{
$this->forUpdate->append($tableName);
}
return $this;
}
/**
* Sets the FOR SHARE lock on select's output row
*
* @param string $tableName The table to lock
* @param string $glue The glue by which to join the conditions. Defaults to ',' .
*
* @return $this
*
* @since 2.0.0
*/
public function forShare($tableName, $glue = ',')
{
$this->type = 'forShare';
if ($this->forShare === null)
{
$glue = strtoupper($glue);
$this->forShare = new QueryElement('FOR SHARE', 'OF ' . $tableName, "$glue ");
}
else
{
$this->forShare->append($tableName);
}
return $this;
}
/**
* Aggregate function to get input values concatenated into a string, separated by delimiter
*
* Usage:
* $query->groupConcat('id', ',');
*
* @param string $expression The expression to apply concatenation to, this may be a column name or complex SQL statement.
* @param string $separator The delimiter of each concatenated value
*
* @return string Input values concatenated into a string, separated by delimiter
*
* @since 2.0.0
*/
public function groupConcat($expression, $separator = ',')
{
return 'string_agg(' . $expression . ', ' . $this->quote($separator) . ')';
}
/**
* Used to get a string to extract year from date column.
*
* Usage:
* $query->select($query->year($query->quoteName('dateColumn')));
*
* @param string $date Date column containing year to be extracted.
*
* @return string Returns string to extract year from a date.
*
* @since 2.0.0
*/
public function year($date)
{
return 'EXTRACT (YEAR FROM ' . $date . ')';
}
/**
* Used to get a string to extract month from date column.
*
* Usage:
* $query->select($query->month($query->quoteName('dateColumn')));
*
* @param string $date Date column containing month to be extracted.
*
* @return string Returns string to extract month from a date.
*
* @since 2.0.0
*/
public function month($date)
{
return 'EXTRACT (MONTH FROM ' . $date . ')';
}
/**
* Used to get a string to extract day from date column.
*
* Usage:
* $query->select($query->day($query->quoteName('dateColumn')));
*
* @param string $date Date column containing day to be extracted.
*
* @return string Returns string to extract day from a date.
*
* @since 2.0.0
*/
public function day($date)
{
return 'EXTRACT (DAY FROM ' . $date . ')';
}
/**
* Used to get a string to extract hour from date column.
*
* Usage:
* $query->select($query->hour($query->quoteName('dateColumn')));
*
* @param string $date Date column containing hour to be extracted.
*
* @return string Returns string to extract hour from a date.
*
* @since 2.0.0
*/
public function hour($date)
{
return 'EXTRACT (HOUR FROM ' . $date . ')';
}
/**
* Used to get a string to extract minute from date column.
*
* Usage:
* $query->select($query->minute($query->quoteName('dateColumn')));
*
* @param string $date Date column containing minute to be extracted.
*
* @return string Returns string to extract minute from a date.
*
* @since 2.0.0
*/
public function minute($date)
{
return 'EXTRACT (MINUTE FROM ' . $date . ')';
}
/**
* Used to get a string to extract seconds from date column.
*
* Usage:
* $query->select($query->second($query->quoteName('dateColumn')));
*
* @param string $date Date column containing second to be extracted.
*
* @return string Returns string to extract second from a date.
*
* @since 2.0.0
*/
public function second($date)
{
return 'EXTRACT (SECOND FROM ' . $date . ')';
}
/**
* Sets the NOWAIT lock on select's output row
*
* @return $this
*
* @since 2.0.0
*/
public function noWait()
{
$this->type = 'noWait';
if ($this->noWait === null)
{
$this->noWait = new QueryElement('NOWAIT', null);
}
return $this;
}
/**
* Set the LIMIT clause to the query
*
* @param integer $limit Number of rows to return
*
* @return $this
*
* @since 2.0.0
*/
public function limit($limit = 0)
{
if ($this->limit === null)
{
$this->limit = new QueryElement('LIMIT', (int) $limit);
}
return $this;
}
/**
* Set the OFFSET clause to the query
*
* @param integer $offset An integer for skipping rows
*
* @return $this
*
* @since 2.0.0
*/
public function offset($offset = 0)
{
if ($this->offset === null)
{
$this->offset = new QueryElement('OFFSET', (int) $offset);
}
return $this;
}
/**
* Add the RETURNING element to INSERT INTO statement.
*
* @param mixed $pkCol The name of the primary key column.
*
* @return $this
*
* @since 2.0.0
*/
public function returning($pkCol)
{
if ($this->returning === null)
{
$this->returning = new QueryElement('RETURNING', $pkCol);
}
return $this;
}
/**
* 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 $offset The offset for the result set
*
* @return string
*
* @since 2.0.0
*/
public function processLimit($query, $limit, $offset = 0)
{
if ($limit > 0)
{
$query .= ' LIMIT ' . $limit;
}
if ($offset > 0)
{
$query .= ' OFFSET ' . $offset;
}
return $query;
}
/**
* 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 string $date The db quoted string representation of the date to add to
* @param string $interval The string representation of the appropriate number of units
* @param string $datePart The part of the date to perform the addition on
*
* @return string The string with the appropriate sql for addition of dates
*
* @since 2.0.0
* @link http://www.postgresql.org/docs/9.0/static/functions-datetime.html.
*/
public function dateAdd($date, $interval, $datePart)
{
if (substr($interval, 0, 1) !== '-')
{
return 'timestamp ' . $date . " + interval '" . $interval . ' ' . $datePart . "'";
}
return 'timestamp ' . $date . " - interval '" . ltrim($interval, '-') . ' ' . $datePart . "'";
}
/**
* Get the regular expression operator
*
* Usage:
* $query->where('field ' . $query->regexp($search));
*
* @param string $value The regex pattern.
*
* @return string
*
* @since 2.0.0
*/
public function regexp($value)
{
return ' ~* ' . $value;
}
/**
* Get the function to return a random floating-point value
*
* Usage:
* $query->rand();
*
* @return string
*
* @since 2.0.0
*/
public function rand()
{
return ' RANDOM() ';
}
/**
* Find a value in a varchar used like a set.
*
* Ensure that the value is an integer before passing to the method.
*
* Usage:
* $query->findInSet((int) $parent->id, 'a.assigned_cat_ids')
*
* @param string $value The value to search for.
* @param string $set The set of values.
*
* @return string A representation of the MySQL find_in_set() function for the driver.
*
* @since 2.0.0
*/
public function findInSet($value, $set)
{
return " $value = ANY (string_to_array($set, ',')::integer[]) ";
}
}