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From Harunobu Oyama ...@telensa.com>
Subject Re: Aggregate function
Date Fri, 15 Jul 2016 17:58:29 GMT
John,

So, there is no Cayenne native way to perform a query such as SELECT
MAX("reading_id") FROM "reading"  ?
It sounds like you are recommending to write another query to fetch a
record with max reading_id instead.

Indeed, the code below worked.

  SQLTemplate query = new SQLTemplate( Reading.class, "SELECT * FROM
\"reading\" WHERE \"reading_id\"=( SELECT MAX(\"reading_id\") FROM
\"reading\" )" );
  List result = context.performQuery( query );

thank you,
nobu




On 15 July 2016 at 18:35, John Huss <johnthuss@gmail.com> wrote:

> Make sure your sqltemplate us set to fetch datarows (hashmap) not objects
> On Fri, Jul 15, 2016 at 12:27 PM Harunobu Oyama <ho@telensa.com> wrote:
>
> > Michael,
> >
> > The min connection and max connection are both 1 as default.
> >
> > nobu
> >
> >
> > On 15 July 2016 at 18:16, Michael Gentry <blacknext@gmail.com> wrote:
> >
> > > On Fri, Jul 15, 2016 at 12:39 PM, Harunobu Oyama <ho@telensa.com>
> wrote:
> > >
> > > > Caused by: java.sql.SQLException: Can't obtain connection. Request
> > timed
> > > > out. Total used connections: 1
> > > > at
> > > >
> > > >
> > >
> >
> org.apache.cayenne.conn.PoolManager.uncheckPooledConnection(PoolManager.java:454)
> > > > at
> > > org.apache.cayenne.conn.PoolManager.getConnection(PoolManager.java:382)
> > > > at
> > > org.apache.cayenne.conn.PoolManager.getConnection(PoolManager.java:371)
> > > > at
> > > >
> > > >
> > >
> >
> org.apache.cayenne.configuration.server.DefaultDbAdapterFactory.detectAdapter(DefaultDbAdapterFactory.java:97)
> > > > ... 15 more
> > >
> > >
> > > Hi Nobu,
> > >
> > > Given this part of the exception, it seems it was unable to get a
> > > connection to the database.  How is your connection pool configured?
> Do
> > > you only have one connection?
> > >
> > > mrg
> > >
> >
>

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