[bdbxml] "Pure" XPath2 versus XQuery
"Kiril Stankov" <[email protected]> Wed, 22 Feb 2006 00:14:24 +0200
| Newsgroups | gmane.comp.db.dbxml.general |
|---|---|
| Message-ID | <[email protected]> |
--=__Part90B225D0.0__= Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi all, =20 I wonder if there is performance difference (or other pros and cons) when = executing simple queries as XPath or XQuery. Example: =20 /Item[@type=3D'Mail' and days-from-duration(fn:current-date()-xs:date(/Item= /CreationTime)) <=3D 7] =20 versus =20 for $x in /Item[@type=3D'Mail'] where days-from-duration(fn:current-date()-xs:date($x/CreationTime)) <=3D = 5 return $x =20 I examined the query plans and they both seem almost same... Well, this is a simple example, but should I always prefer XPath, if it = does the job? =20 TIA, =20 Kiril. =20 --=__Part90B225D0.0__= Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Description: HTML <HTML><HEAD> <META http-equiv=3DContent-Type content=3D"text/html; charset=3Dutf-8"> <META content=3D"MSHTML 6.00.3790.2577" name=3DGENERATOR></HEAD> <BODY style=3D"MARGIN: 4px 4px 1px; FONT: 10pt Trebuchet MS"> <DIV>Hi all,</DIV> <DIV> </DIV> <DIV>I wonder if there is performance difference (or other pros and = cons) when executing simple queries as XPath or XQuery.</DIV> <DIV>Example:</DIV> <DIV> </DIV> <DIV>/Item[@type=3D'Mail' and days-from-duration(fn:current-date()-xs:date(= /Item/CreationTime)) <=3D 7]</DIV> <DIV> </DIV> <DIV>versus</DIV> <DIV> </DIV> <DIV>for $x in /Item[@type=3D'Mail']<BR>where days-from-duration(fn:current= -date()-xs:date($x/CreationTime)) <=3D 5<BR>return $x</DIV> <DIV> </DIV> <DIV>I examined the query plans and they both seem almost same...</DIV> <DIV>Well, this is a simple example, but should I always prefer XPath, if = it does the job?</DIV> <DIV> </DIV> <DIV>TIA,</DIV> <DIV> </DIV> <DIV>Kiril.</DIV> <DIV> </DIV></BODY></HTML> --=__Part90B225D0.0__=--