带有超时的JDBC postgres查询

Question

Unfortunately setTimeout is not implemented for JDBC/postgres. Is there some way I can simulate or workaround this? Functionally I want to execute the query and the then break if it takes longer than N seconds

Answer 1

The "statement_timeout" looks like what you want.

SET statement_timeout TO 1000; -- for a second
<your_query_here>;
RESET statement_timeout; -- reset

Answer 2

One way might be to try running the query in a Timer class. Throw an exception if the Timer ends without a value returned.

Hibernate and JDO supply such a construct. Maybe they'd be good alternatives for you.

Answer 3

What if you were to use c3p0 for your dataSource? It has lots of configurable options, and for cranky databases and networks, for example, acquireRetryAttempts, acquireRetryDelay, and breakAfterAcquireFailure.

Answer 4

Using the LOCAL keyword limits the scope of the statement_timeout to the current transaction. That way, if anything goes wrong (eg it times out) the timeout gets reset.

BEGIN TRANSACTION;
SET LOCAL statement_timeout TO 1000;    -- one-second timeout
SELECT COUNT(*) FROM really_huge_table; -- your slow query
ROLLBACK;                               -- reset