问题:

I want to select date in particular format in multiselect of jpa criteria query like we use

select to_char(tn.dbdate,'yyyy-MM-dd') from transaction tn

in oracle.

I am able to use

query.multiselect(cb.function("TO_CHAR",String.class,transaction.get("dbdate")) );

but this returns date in database format i.e.

Wed Apr 2 12:20:50 2014

but how to get this in specific date format

'yyyy-MM-dd'

回答1:

In current query no format is given as an argument to TO_CHAR function. That's why it cannot do much else than fall back to default. As documented, more than one arguments can also be passed to database function via CriteriaBuilder.function:

query.multiselect(
    cb.function("TO_CHAR",
                String.class,transaction.get("dbdate"), 
                cb.literal("yyyy-MM-dd")));

回答2:

You can take the date from DB and format it as you want later.

回答3:

This worked for me:

Expression<String> dateStringExpr = cb.function("to_char", String.class,
        root.get("effectiveStartDate"), cb.literal("YYYY-MM-DD HH12:MI:SS"));

ls.add(cb.like(cb.lower(dateStringExpr), "%" + effectiveStartDate.get().toLowerCase() + "%"));