Re: Insert data if it is not existing

On 05/23/2018 04:58 PM, tango ward wrote:

Thanks masters for responding again.

I've tried running the code:

INSERT INTO my_table(name, age)
SELECT name, age
WHERE NOT EXISTS(SELECT name FROM my_table WHERE name= name)

The first thing I see is that:

SELECT name, age

is not being selected from anywhere, for example:

SELECT name, age FROM some_table.

The second thing I see is why not use ON CONFLICT?

this doesn't give me error but it doesn't insert data either.

On Thu, May 24, 2018 at 3:35 AM, Adrian Klaver <adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>> wrote:

    On 05/23/2018 10:00 AM, David G. Johnston wrote:

        On Wednesday, May 23, 2018, tango ward <tangoward15@gmail.com
        <mailto:tangoward15@gmail.com> <mailto:tangoward15@gmail.com
        <mailto:tangoward15@gmail.com>>> wrote:

             I just want to ask if it's possible to insert data if it's not
             existing yet.


        This seems more like a philosophical question than a technical
        one...
        ​but the answer is yes:

        CREATE TABLE test_t (a varchar, b varchar, c integer);
        INSERT INTO test_t
        SELECT '1', '2', 3 WHERE false;​ --where false causes the data
        to effectively "not exist"

        As for ON CONFLICT: conflicts can only happen between things
        that exist.


    Well that made my day:)


        David J.



    --     Adrian Klaver
    adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>

--
Adrian Klaver
adrian.klaver@aklaver.com