FEATURE: added datetime helper functions

This commit is contained in:
Andreas Piening 2010-02-03 05:01:37 +00:00
parent 27975ad20f
commit 9c1bda45ff

View File

@ -1361,6 +1361,131 @@ class MSSQLDatabase extends SS_Database {
public function endTransaction(){
//Transactions not set up for MSSQL yet
}
/**
* Function to return an SQL datetime expression that can be used with SQLite3
* used for querying a datetime in a certain format
* @param string $date to be formated, can be either 'now', literal datetime like '1973-10-14 10:30:00' or field name, e.g. '"SiteTree"."Created"'
* @param string $format to be used, supported specifiers:
* %Y = Year (four digits)
* %m = Month (01..12)
* %d = Day (01..31)
* %H = Hour (00..23)
* %i = Minutes (00..59)
* %s = Seconds (00..59)
* %U = unix timestamp, can only be used on it's own
* @return string SQL datetime expression to query for a formatted datetime
*/
function formattedDatetimeClause($date, $format) {
preg_match_all('/%(.)/', $format, $matches);
foreach($matches[1] as $match) if(array_search($match, array('Y','m','d','H','i','s','U')) === false) user_error('formattedDatetimeClause(): unsupported format character %' . $match, E_USER_WARNING);
if(preg_match('/^now$/i', $date)) {
$date = "CURRENT_TIMESTAMP";
} else if(preg_match('/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/i', $date)) {
$date = "'$date'";
}
if($format == '%U') return "DATEDIFF(s, '19700101', $date)";
$trans = array(
'Y' => 'yy',
'm' => 'mm',
'd' => 'dd',
'H' => 'hh',
'i' => 'mi',
's' => 'ss',
);
$strings = array();
$buffer = $format;
while(strlen($buffer)) {
if(substr($buffer,0,1) == '%') {
$f = substr($buffer,1,1);
$flen = $f == 'Y' ? 4 : 2;
$strings[] = "RIGHT('0' + CAST(DATEPART({$trans[$f]},$date) AS VARCHAR), $flen)";
$buffer = substr($buffer, 2);
} else {
$pos = strpos($buffer, '%');
if($pos === false) {
$strings[] = $buffer;
$buffer = '';
} else {
$strings[] = "'".substr($buffer, 0, $pos)."'";
$buffer = substr($buffer, $pos);
}
}
}
return '(' . implode(' + ', $strings) . ')';
}
/**
* Function to return an SQL datetime expression that can be used with SQLite3
* used for querying a datetime addition
* @param string $date, can be either 'now', literal datetime like '1973-10-14 10:30:00' or field name, e.g. '"SiteTree"."Created"'
* @param string $interval to be added, use the format [sign][integer] [qualifier], e.g. -1 Day, +15 minutes, +1 YEAR
* supported qualifiers:
* - years
* - months
* - days
* - hours
* - minutes
* - seconds
* This includes the singular forms as well
* @return string SQL datetime expression to query for a datetime (YYYY-MM-DD hh:mm:ss) which is the result of the addition
*/
function datetimeIntervalClause($date, $interval) {
$trans = array(
'year' => 'yy',
'month' => 'mm',
'day' => 'dd',
'hour' => 'hh',
'minute' => 'mi',
'second' => 'ss',
);
$singularinterval = preg_replace('/(year|month|day|hour|minute|second)s/i', '$1', $interval);
if(
!($params = preg_match('/([-+]\d+) (\w+)/i', $singularinterval, $matches)) ||
!isset($trans[strtolower($matches[2])])
) user_error('datetimeIntervalClause(): invalid interval ' . $interval, E_USER_WARNING);
if(preg_match('/^now$/i', $date)) {
$date = "CURRENT_TIMESTAMP";
} else if(preg_match('/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/i', $date)) {
$date = "'$date'";
}
return "LEFT(CONVERT(VARCHAR, DATEADD(" . $trans[strtolower($matches[2])] . ", " . (int)$matches[1] . ", $date), 121), 19)";
}
/**
* Function to return an SQL datetime expression that can be used with SQLite3
* used for querying a datetime substraction
* @param string $date1, can be either 'now', literal datetime like '1973-10-14 10:30:00' or field name, e.g. '"SiteTree"."Created"'
* @param string $date2 to be substracted of $date1, can be either 'now', literal datetime like '1973-10-14 10:30:00' or field name, e.g. '"SiteTree"."Created"'
* @return string SQL datetime expression to query for the interval between $date1 and $date2 in seconds which is the result of the substraction
*/
function datetimeDifferenceClause($date1, $date2) {
if(preg_match('/^now$/i', $date1)) {
$date1 = "CURRENT_TIMESTAMP";
} else if(preg_match('/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/i', $date1)) {
$date1 = "'$date1'";
}
if(preg_match('/^now$/i', $date2)) {
$date2 = "CURRENT_TIMESTAMP";
} else if(preg_match('/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/i', $date2)) {
$date2 = "'$date2'";
}
return "DATEDIFF(s, $date2, $date1)";
}
}
/**