如何使用JOOQ“选择SQL_NO_CACHE”？

Question

I tried to find a documentation for it, but failed. Anyone knows?

Answer 1

There are several ways to add MySQL-style hints to jOOQ queries:

Using .hint()

jOOQ allows for passing "hints" to SELECT statements via the .hint() method as explained here in the manual:

http://www.jooq.org/doc/latest/manual/sql-building/sql-statements/select-statement/oracle-hints

Applying the SQL_NO_CACHE hint to the example given in the manual, you'd get:

DSL.using(configuration)
   .select(field1, field2)
   .hint("SQL_NO_CACHE")
   .from(table1)
   .fetch();

Using plain SQL

You could use plain SQL to tweak the first field in your SELECT clause to contain the hint using DSL.field(String) . Eg

DSL.using(configuration)
   .select(DSL.field("SQL_NO_CACHE {0}", field1.getDataType(), field1), field2)
   .from(table1)
   .fetch();

Using ExecuteListener or VisitListener

You could inject an ExecuteListener or a VisitListener into your configuration in order to transform all relevant SQL query strings to contain the hint right after the SELECT keyword. This will probably be a bit of overkill in your case, but it's worth mentioning this as an option to this kind of problem.