Lucky, If you enable *enforceJoinOrder* option, then join operations will be performed in the exact order, in which they appear in the query. This flag prevents an SQL optimizer from rearranging the tables. This is why some queries may become faster, and some slower.
So, to find an optimal order, you can try rearranging tables in your joins, i.e. changing *a JOIN b* to *b JOIN a*. Denis пт, 1 дек. 2017 г. в 15:30, Denis Mekhanikov <[email protected]>: > Lucky, > > How much data do you retrieve in this query? > There is some overhead, caused by network communication, when you are > using JDBC drivers, but it's not expected to be so big. > Also do you connect over JDBC to the same node, on which you test > IgniteCache#query() ? > > Denis > > чт, 30 нояб. 2017 г. в 11:30, Lucky <[email protected]>: > >> Denis, >> It's worse! >> There just have several sql can be faster, the other took more time. >> Thanks. >> >> >> >> >> >> 在 2017-11-29 21:31:05，"Denis Mekhanikov" <[email protected]> 写道： >> >> Lucky, >> >> Try enabling *enforceJoinOrder *parameter in JDBC connection string and >> let us know the result. >> Your JDBC connection string should look like this: >> jdbc:ignite:thin://127.0.0.1?*enforceJoinOrder=true* >> >> Denis >> >>> >>>
