I have data from a postgres tables that looks like this:
Server | Database | Contact
server1 | db1 | contact 1
server1 | db2 | contact 2
server1 | db3 | contact 3
server2 | db1 | contact 4
server2 | db2 | contact 3
But I need to transform it to pass to a front end view in this format:
Server | Database | Contact
server1 | {db1, db2, db3} | {contact1, contact2, contact3}
server2 | {db1, db2} | {contact3, contact4}
For every unique value in the Server
column I want to create an array column out of every other column in my SQL query. So far I have something like this but it does not seem to create an array out of the Server
column (Contact column excluded for clarity):
SELECT "table1"."Server"
COALESCE( NULLIF( array
(
select DISTINCT x
FROM unnest( array_agg(DISTINCT "table1"."Server") ) x
WHERE x IS NOT NULL ), '{}' ), '{"No Data"}' ) AS "serverList" ,
COALESCE( NULLIF( array
(
SELECT x
FROM unnest( array_agg(DISTINCT "table1"."Database") ) x
WHERE x IS NOT NULL ), '{}' ), '{"No Data"}' ) AS "databseList"
FROM "table1"
GROUP BY
"table1"."Server"
How can I correctly create array columns out of unique entries in the Server column?
How about array_agg()
?
select server, array_agg(database) as databases, array_agg(contact) as contacts
from t
group by server;
If the values need to be unique in the arrays, use distinct
.