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Tatiana When you are talking to Qserv, the front end that you are talking to is mysql proxy (which looks exactly like standard mysql on the surface). Under the hood, we are intercepting each query and do all sorts of somewhat uncommon things. The bottom line is that "select columns from %table%' from mysql" will not give you what is expected, because were is currently not handled by qserv/mysqlProxy. Regarding the issue with DeepCoadd, I vaguely recall DeepCoadd is a view, and there were some issues with views in the past. Looking at the log files from qserv czar and xrootd would help understand this problem, do you know where to look? Jacek On 11/11/2014 12:27 PM, Tatiana Goldina wrote: > Thank you for a quick reply. > > I am issuing "select columns from %table%' from mysql command line > client. For now this is the only client that I know which can connect > to QSERVE mysql proxy. It could be that MySQL Query Browser and > IntelliJ (via JDBC driver) fail to connect because in addition to > connecting they try to get extra information about the the schema. I'll > test it tonight. > > The other issue is that I can not make any of the select statements > work. It appears to hang for a long while, then produces an error. For > example, how do I get a row count for a table? > > mysql> select count(deepCoaddId) from DeepCoadd; > ERROR 4120 (Proxy): Error executing query using qserv. > > Tatiana > > On Nov 11, 2014, at 10:14 AM, Serge Monkewitz <[log in to unmask] > <mailto:[log in to unmask]>> wrote: > >> Hi Tatiana, >> >> I’m moving this discussions to the qserv mailing list. There’s a >> page on the SQL constructs that qserv supports here: >> https://dev.lsstcorp.org/trac/wiki/db/ScalableArchSQL. >> >> In general, it’s SQL 92 minus sub-queries, and with some spatial >> support. That means that MySQL specific syntax usually isn’t >> supported. Unfortunately, I’m not aware of a page that lists out the >> exact MySQLisms that we do support, but I believe it’s limited to: >> >> SHOW TABLES >> SHOW DATABSES >> DESCRIBE >> >> Are you saying that the JDBC driver itself is issuing SHOW COLUMNS, or >> is that initiated on your end? >> >> Cheers, >> Serge >> >> Begin forwarded message: >> >>> *From: *Tatiana Goldina <[log in to unmask] >>> <mailto:[log in to unmask]>> >>> *Subject: **connecting to qserv database* >>> *Date: *November 11, 2014 at 9:07:02 AM PST >>> *To: *Serge Monkewitz <[log in to unmask] >>> <mailto:[log in to unmask]>> >>> >>> Hi Serge, >>> >>> John Rector has set a QSERV for us here at IPAC, and we are trying >>> to figure out how to access it. >>> >>> It seems that I can not access it with a MySql GUI client or JDBC >>> (jdbc:mysql://lsst-db1.ipac.caltech.edu >>> <http://lsst-db1.ipac.caltech.edu/>:4040/LSST) >>> >>> I am able to access it with command line mysql client. I can get the >>> tables with "show tables;" but >>> >>> mysql> show columns from DeepSource from LSST; >>> ERROR 4110 (Proxy): Qserv error: 'ParseException:ANTLR parse >>> error:unexpected token: show:' >>> >>> (The same error that we get when trying to connect with JDBC.) >>> >>> On the other hand "describe DeepSource;" works. >>> >>> How do I find out which commands are supported? >>> >>> Tatiana >> > > > ------------------------------------------------------------------------ > > Use REPLY-ALL to reply to list > > To unsubscribe from the QSERV-L list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=QSERV-L&A=1 > ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the QSERV-L list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=QSERV-L&A=1