Обсуждение: update question
<div id="RTEContent">I need a throw away value for an insert statement... example...<br /><br /> update table<br /> set value= 1, value = 2, throw_away_value -- so i don't break the query<br /> where id = 1; <br /><br /> Thanks<br /></div><p><hrsize="1" /><b>Yahoo! Personals</b><br /> Let fate take it's course directly to your email.<br /> See who'swaiting for you <a href="http://us.rd.yahoo.com/evt=36106/*http://personals.yahoo.com ">Yahoo! Personals</a>
On 12/5/05, Matthew Peter <survivedsushi@yahoo.com> wrote: > I need a throw away value for an insert statement... example... > > update table > set value = 1, value = 2, throw_away_value -- so i don't break the query > where id = 1; > > Thanks > What do you mean by "throw away value"? are you trying to update and if the row doesn't exist then insert? if that is you can do a function in plpgsql and use exceptions for that... there is an example in the manuals -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)
<div id="RTEContent">it's in a loop so there's an extra comma at the end so i was thinking i could put in a throw away valueto keep the update from breaking if there's an additional comma<br /><br /><b><i>Jaime Casanova <systemguards@gmail.com></i></b>wrote:<blockquote class="replbq" style="border-left: 2px solid rgb(16, 16, 255); margin-left:5px; padding-left: 5px;"> On 12/5/05, Matthew Peter wrote:<br />> I need a throw away value for an insertstatement... example...<br />><br />> update table<br />> set value = 1, value = 2, throw_away_value -- soi don't break the query<br />> where id = 1;<br />><br />> Thanks<br />><br /><br />What do you mean by "throwaway value"?<br /><br />are you trying to update and if the row doesn't exist then insert? if<br />that is you cando a function in plpgsql and use exceptions for<br />that... there is an example in the manuals<br /><br />--<br />regards,<br/>Jaime Casanova<br />(DBA: DataBase Aniquilator ;)<br /><br />---------------------------(end of broadcast)---------------------------<br/>TIP 4: Have you searched our list archives?<br /><br /> http://archives.postgresql.org<br/></blockquote><br /></div><p><hr size="1" /><b>Yahoo! Personals</b><br /> Single? There'ssomeone we'd like you to meet.<br /> Lots of someones, actually. <a href="http://us.rd.yahoo.com/evt=36108/*http://personals.yahoo.com ">Yahoo! Personals</a>
<div id="RTEContent">Like WHERE 1 = 1, but in UPDATE table SET value = 1, 1 = 1;<br /></div><p><hr size="1" /><b>Yahoo! Personals</b><br/> Single? There's someone we'd like you to meet.<br /> Lots of someones, actually. <a href="http://us.rd.yahoo.com/evt=36108/*http://personals.yahoo.com ">Try Yahoo! Personals</a>
On 12/5/05, Matthew Peter <survivedsushi@yahoo.com> wrote: > it's in a loop so there's an extra comma at the end so i was thinking i > could put in a throw away value to keep the update from breaking if there's > an additional comma > > Jaime Casanova <systemguards@gmail.com> wrote: > On 12/5/05, Matthew Peter wrote: > > I need a throw away value for an insert statement... example... > > > > update table > > set value = 1, value = 2, throw_away_value -- so i don't break the query > > where id = 1; > > > > Thanks > > > i guess you are constructing the query in a string and EXECUTEd it... if that is the case review your logic... -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)
Matthew Peter <survivedsushi@yahoo.com> writes:
> it's in a loop so there's an extra comma at the end so i was thinking i could put in a throw away value to keep the
updatefrom breaking if there's an additional comma
The best thing is to fix your loop logic. Usually it's not hard to emit
a comma only if one is needed.
If you're intent on using a broken loop, you could do "foo = foo" where
foo is any table column you didn't yet assign to. Consider though the
corner case where you've already assigned all the columns. Best bet
is to fix your loop...
regards, tom lane