Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
722 views
in Technique[技术] by (71.8m points)

mysql - How can I pass an "array" of values to my stored procedure?

I want to be able to pass an "array" of values to my stored procedure, instead of calling "Add value" procedure serially.

Can anyone suggest a way to do it? am I missing something here?

Edit: I will be using PostgreSQL / MySQL, I haven't decided yet.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

As Chris pointed, in PostgreSQL it's no problem - any base type (like int, text) has it's own array subtype, and you can also create custom types including composite ones. For example:

CREATE TYPE test as (
    n int4,
    m int4
);

Now you can easily create array of test:

select ARRAY[
    row(1,2)::test,
    row(3,4)::test,
    row(5,6)::test
];

You can write a function that will multiply n*m for each item in array, and return sum of products:

CREATE OR REPLACE FUNCTION test_test(IN work_array test[]) RETURNS INT4 as $$
DECLARE
    i      INT4;
    result INT4 := 0;
BEGIN
    FOR i IN SELECT generate_subscripts( work_array, 1 ) LOOP
        result := result + work_array[i].n * work_array[i].m;
    END LOOP;
    RETURN result;
END;
$$ language plpgsql;

and run it:

# SELECT test_test(
    ARRAY[
        row(1, 2)::test,
        row(3,4)::test,
        row(5,6)::test
    ]
);
 test_test
-----------
        44
(1 row)

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...