jOOQ insert into .. where not exists for Postgres

问题

I'm attempting to do an upsert-style statement for Postgres in jOOQ. The framework I'm running in takes care of concurrency concerns in this specific situation so I'm not worried about that. I'm only using jOOQ for creating the SQL, the actual execution is done via Spring's JdbcTemplate and a BeanPropertySqlParameterSource.

I've decided to go with a two-step "insert..where not exists" / "update .." process.

My SQL is:

insert into mytable (my_id, col1, col2) select :myId, 
   :firstCol, :secondCol where not exists (select 1 
   from mytable where my_id = :myId)

I'm using Postgres 9.4, jOOQ 3.5. I'm not sure how to express both the jOOQ params in the select and the "where not exists" clause in jOOQ.

Suggestions to change programming languages or databases aren't viable in my situation.

回答1:

If you want to reuse a named parameter in jOOQ, ideally, you create the AST element outside of the query, as such:

// Assuming a static import
import static org.jooq.impl.DSL.*;

Param<Integer> myId = param("myId", Integer.class);

You can then use it multiple times in your query:

using(configuration)
  .insertInto(MY_TABLE, MY_TABLE.MY_ID, MY_TABLE.COL1, MY_TABLE.COL2)
  .select(
     select(
        myId, 
        param("firstCol", MY_TABLE.COL1.getType()),
        param("secondCol", MY_TABLE.COL2.getType())
     )
     .whereNotExists(
        selectOne()
        .from(MY_TABLE)
        .where(MY_TABLE.MY_ID.eq(myId))
     )
  );

来源：https://stackoverflow.com/questions/29569846/jooq-insert-into-where-not-exists-for-postgres

标签

postgresql

jooq