Informix defining an INTERVAL with a parameter

问题

I am doing the following in Informix to delete rows more than 20 seconds old.

delete from sometable
where someDateColumn < (current - interval (20) second to second);

However, I want to make the interval configurable in a stored procedure, but I can't do

CREATE PROCEDURE i_hate_informix (prm_timeframe int)
    DELETE   sometable
    WHERE    someDateColumn < (current - interval (prm_timeframe) second to second);
END PROCEDURE;

回答1:

I found the answer myself.

Interval can not be defined dynamically with a variable. But you can use "units second" so my procedure becomes

CREATE PROCEDURE i_hate_informix (prm_timeframe int)
   DELETE   sometable
   WHERE    someDateColumn < (current - prm_timeframe units second);
END PROCEDURE;

来源：https://stackoverflow.com/questions/920207/informix-defining-an-interval-with-a-parameter