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Thread: Use multidimensional array as VALUES clause in insert

Use multidimensional array as VALUES clause in insert

From
Mike Martin
Date:
Is this possible? I have seen examples with array literals as VALUES string, but I cant seen to get it to work with an actual array.

testing code

--This gets me a multidimensional array
with arr AS (
SELECT ARRAY(SELECT ARRAY[fileid::text,tagname,array_to_string(tagvalue,E'\b')]
FROM tagdata_all) -- limit 100)
arr1
)
--Then

INSERT INTO  tagdatatest2
SELECT  arr1::text[] FROM arr --doesnt work only populates one column with original array


Re: Use multidimensional array as VALUES clause in insert

From
"David G. Johnston"
Date:
On Tuesday, August 11, 2020, Mike Martin <redtux1@gmail.com> wrote:
Is this possible? I have seen examples with array literals as VALUES string, but I cant seen to get it to work with an actual array.

testing code

--This gets me a multidimensional array
with arr AS (
SELECT ARRAY(SELECT ARRAY[fileid::text,tagname,array_to_string(tagvalue,E'\b')]
FROM tagdata_all) -- limit 100)
arr1
)
--Then

INSERT INTO  tagdatatest2
SELECT  arr1::text[] FROM arr --doesnt work only populates one column with original array

There is no simple way to have each element of an array be inserted into a different column nor have each element populate a different row.  You should avoid the multi-dimensional array if at all possible.

David J.

Re: Use multidimensional array as VALUES clause in insert

From
Thomas Kellerer
Date:
Mike Martin schrieb am 11.08.2020 um 12:50:
> Is this possible? I have seen examples with array literals as VALUES string, but I cant seen to get it to work with
anactual array. 
>
> testing code
>
> --This gets me a multidimensional array
> with arr AS (
> SELECT ARRAY(SELECT ARRAY[fileid::text,tagname,array_to_string(tagvalue,E'\b')]
> FROM tagdata_all) -- limit 100)
> arr1
> )
> --Then
>
> INSERT INTO  tagdatatest2
> SELECT  arr1::text[] FROM arr --doesnt work only populates one column with original array

I don't understand why you aggregate in the first place if you want to the insert the array elements as rows.

Can't you just do:

   INSERT INTO  tagdatatest2 (fileid, tagname, tagvalue)
   SELECT fileid, tagname, array_to_string(tagvalue,E'\b')
   FROM tagdata_all

Re: Use multidimensional array as VALUES clause in insert

From
Mike Martin
Date:
The example isn't what I am doing, its just a test to get multidimensional array within db for testing import of array from application (perl in this case)

On Tue, 11 Aug 2020 at 15:08, Thomas Kellerer <shammat@gmx.net> wrote:

Mike Martin schrieb am 11.08.2020 um 12:50:
> Is this possible? I have seen examples with array literals as VALUES string, but I cant seen to get it to work with an actual array.
>
> testing code
>
> --This gets me a multidimensional array
> with arr AS (
> SELECT ARRAY(SELECT ARRAY[fileid::text,tagname,array_to_string(tagvalue,E'\b')]
> FROM tagdata_all) -- limit 100)
> arr1
> )
> --Then
>
> INSERT INTO  tagdatatest2
> SELECT  arr1::text[] FROM arr --doesnt work only populates one column with original array

I don't understand why you aggregate in the first place if you want to the insert the array elements as rows.

Can't you just do:

   INSERT INTO  tagdatatest2 (fileid, tagname, tagvalue)
   SELECT fileid, tagname, array_to_string(tagvalue,E'\b')
   FROM tagdata_all