Re: BUG? res.next() == false, but psql finds tuples?

Certainly looks like a bug, in the java version mango is not quoted so
pg thinks it is a column.

Although I just checked the test cases and we do this all the time ???

Dave

Palle Girgensohn wrote:

> Hi!
>
> Here's something really odd. Is it a bug in the jdbc driver? 8.0.311:
>
>
> String query = "select lang from participant where userid = ?
> and course_id = ?";
> PreparedStatement ps = con.prepareStatement(query);
> ps.setString(1, userId);
> ps.setInt(2, courseId);
> ResultSet res = ps.executeQuery();
>
> System.err.println("[1] "+ps);
>
> boolean hasNext = res.next();
> System.err.println("hasNext: "+hasNext);
>
> if (hasNext) {
> System.err.println("[2]");
> language = res.getString(1);
> System.err.println("language: "+language);
> }
> System.err.println("[3]");
>
> In the java error log:
>
> ---
> [1] select lang from participant where userid = mango and course_id = 38
> hasNext: false
> [3]
> ---
>
>
> but with psql, there's no problem getting a value:
>
> mango=> select lang from participant where userid = 'mango' and
> course_id = 38;
> lang
> ------
> sv
> (1 row)
>
> (Connected to same database as same user.)
>
> What's up? Is there a problem with the (new) prepared statement stuff?
>
> postgresql-8.0.2, postgresql-jdbc-8.0.311, FreeBSD 4.11, java 1.4.2.
>
> /Palle
>
> PS. Here's a tcpdump of the query, FWIW:
>
> 13:37:14.909230 localhost.3277 > localhost.postgresql: P
> 564113356:564113492(136) ack 897123100 win 57344 <nop,nop,timestamp
> 729334714 729334409> (DF)
> 0x0000 4500 00bc 5038 4000 4006 ec01 7f00 0001 E(dot)(dot)(dot)P8(at)(dot)@.......
> 0x0010 7f00 0001 0ccd 1538 219f afcc 3579 031c .......8!...5y..
> 0x0020 8018 e000 6474 0000 0101 080a 2b78 c3ba ....dt......+x..
> 0x0030 2b78 c289 5000 0000 5100 7365 6c65 6374 +x..P...Q.select
> 0x0040 206c 616e 6720 6672 6f6d 2070 6172 7469 .lang.from.parti
> 0x0050 6369 7061 6e74 2077 6865 7265 2075 7365 cipant.where.use
> 0x0060 7269 6420 3d20 2431 2061 6e64 2063 6f75 rid.=.$1.and.cou
> 0x0070 7273 655f 6964 203d 2024 3200 0002 0000 rse_id.=.$2.....
> 0x0080 0413 0000 0017 4200 0000 1f00 0000 0200 ......B.........
> 0x0090 0000 0000 0200 0000 056d 616e 676f 0000 .........mango..
> 0x00a0 0002 3338 0000 4400 0000 0650 0045 0000 ..38..D....P.E..
> 0x00b0 0009 0000 0000 0053 0000 0004 .......S....
> 13:37:14.916554 localhost.postgresql > localhost.3277: P 1:59(58) ack
> 136 win 57344<nop,nop,timestamp 729334715 729334714> (DF)
> 0x0000 4500 006e 5039 4000 4006 ec4e 7f00 0001 E(dot)(dot)nP9(at)(dot)@..N....
> 0x0010 7f00 0001 1538 0ccd 3579 031c 219f b054 .....8..5y..!..T
> 0x0020 8018 e000 4908 0000 0101 080a 2b78 c3bb ....I.......+x..
> 0x0030 2b78 c3ba 3100 0000 0432 0000 0004 5400 +x..1....2....T.
> 0x0040 0000 1d00 016c 616e 6700 0000 4821 0003 .....lang...H!..
> 0x0050 0000 0019 ffff ffff ffff 0000 4300 0000 ............C...
> 0x0060 0b53 454c 4543 5400 5a00 0000 0549 .SELECT.Z....I
>
>
>
> And here's one from psql (that works fine, result = 'sv'):
>
> 15:16:40.179908 localhost.1973 > localhost.postgresql: P 82:159(77)
> ack 294 win 57344 <nop,nop,timestamp 729931235 729930768> (DF)
> 0x0000 4500 0081 f57e 4000 4006 46f6 7f00 0001 E(dot)(dot)(dot)(dot)~(at)(dot)@.F.....
> 0x0010 7f00 0001 07b5 1538 3c3c 839d 3a40 cc42 .......8<<..:@.B
> 0x0020 8018 e000 77ae 0000 0101 080a 2b81 dde3 ....w.......+...
> 0x0030 2b81 dc10 5100 0000 4c73 656c 6563 7420 +...Q...Lselect.
> 0x0040 6c61 6e67 2066 726f 6d20 7061 7274 6963 lang.from.partic
> 0x0050 6970 616e 7420 7768 6572 6520 7573 6572 ipant.where.user
> 0x0060 6964 203d 2027 6d61 6e67 6f27 2061 6e64 id.=.'mango'.and
> 0x0070 2063 6f75 7273 655f 6964 203d 2033 383b .course_id.=.38;
> 0x0080 00 .
> 15:16:40.183568 localhost.postgresql > localhost.1973: P 294:355(61)
> ack 159 win 57344 <nop,nop,timestamp 729931236 729931235> (DF)
> 0x0000 4500 0071 f580 4000 4006 4704 7f00 0001 E(dot)(dot)q(dot)(dot)(at)(dot)@.G.....
> 0x0010 7f00 0001 1538 07b5 3a40 cc42 3c3c 83ea .....8..:@.B<<..
> 0x0020 8018 e000 28fb 0000 0101 080a 2b81 dde4 ....(.......+...
> 0x0030 2b81 dde3 5400 0000 1d00 016c 616e 6700 +...T......lang.
> 0x0040 0000 4821 0003 0000 0019 ffff ffff ffff ..H!............
> 0x0050 0000 4400 0000 0c00 0100 0000 0273 7643 ..D..........svC
> 0x0060 0000 000b 5345 4c45 4354 005a 0000 0005 ....SELECT.Z....
> 0x0070 49 I
>
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 3: if posting/reading through Usenet, please send an appropriate
> subscribe-nomail command to majordomo(at)postgresql(dot)org so that your
> message can get through to the mailing list cleanly
>
>

--
Dave Cramer
http://www.postgresintl.com
519 939 0336
ICQ#14675561