how to join several row values in one row in postgresql? [duplicate] - sql

Question

I have a table and I'd like to pull one row per id with field values concatenated.
In my table, for example, I have this:
TM67 | 4 | 32556
TM67 | 9 | 98200
TM67 | 72 | 22300
TM99 | 2 | 23009
TM99 | 3 | 11200
And I'd like to output:
TM67 | 4,9,72 | 32556,98200,22300
TM99 | 2,3 | 23009,11200
In MySQL I was able to use the aggregate function GROUP_CONCAT, but that doesn't seem to work here... Is there an equivalent for PostgreSQL, or another way to accomplish this?

Answer 1

Since 9.0 this is even easier:
SELECT id,
string_agg(some_column, ',')
FROM the_table
GROUP BY id

Answer 2

This is probably a good starting point (version 8.4+ only):
SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field
array_agg returns an array, but you can CAST that to text and edit as needed (see clarifications, below).
Prior to version 8.4, you have to define it yourself prior to use:
CREATE AGGREGATE array_agg (anyelement)
(
sfunc = array_append,
stype = anyarray,
initcond = '{}'
);
(paraphrased from the PostgreSQL documentation)
Clarifications:
The result of casting an array to text is that the resulting string starts and ends with curly braces. Those braces need to be removed by some method, if they are not desired.
Casting ANYARRAY to TEXT best simulates CSV output as elements that contain embedded commas are double-quoted in the output in standard CSV style. Neither array_to_string() or string_agg() (the "group_concat" function added in 9.1) quote strings with embedded commas, resulting in an incorrect number of elements in the resulting list.
The new 9.1 string_agg() function does NOT cast the inner results to TEXT first. So "string_agg(value_field)" would generate an error if value_field is an integer. "string_agg(value_field::text)" would be required. The array_agg() method requires only one cast after the aggregation (rather than a cast per value).

Answer 3

SELECT array_to_string(array(SELECT a FROM b),', ');
Will do as well.

Answer 4

Try like this:
select field1, array_to_string(array_agg(field2), ',')
from table1
group by field1;

Answer 5

Assuming that the table your_table has three columns (name, id, value), the query is this one:
select name,
array_to_string(array_agg(id), ','),
array_to_string(array_agg(value), ',')
from your_table
group by name
order by name
;
"TM67" "4,9,72" "32556,98200,22300"
"TM99" "2,3" "23009,11200"
KI

Answer 6

and the version to work on the array type:
select
array_to_string(
array(select distinct unnest(zip_codes) from table),
', '
);

Answer 7

My sugestion in postgresql
SELECT cpf || ';' || nome || ';' || telefone
FROM (
SELECT cpf
,nome
,STRING_AGG(CONCAT_WS( ';' , DDD_1, TELEFONE_1),';') AS telefone
FROM (
SELECT DISTINCT *
FROM temp_bd
ORDER BY cpf DESC ) AS y
GROUP BY 1,2 ) AS x

Answer 8

In my experience, I had bigint as column type. So The below code worked for me. I am using PostgreSQL 12.
Type cast is happening here. (::text).
string_agg(some_column::text, ',')

Answer 9

Hope below Oracle query will work.
Select First_column,LISTAGG(second_column,',')
WITHIN GROUP (ORDER BY second_column) as Sec_column,
LISTAGG(third_column,',')
WITHIN GROUP (ORDER BY second_column) as thrd_column
FROM tablename
GROUP BY first_column