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...P8@.@.......
> 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..nP9@.@..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....~@.@.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..q..@.@.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
>
>
>
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--
Dave Cramer
http://www.postgresintl.com
519 939 0336
ICQ#14675561