In PostgreSQL 9.4, how do I retrieve json object like this:
parentTableFirstProp: 'string',
parentToChildReference: [
{childTableFirstProp: 'another string'},
{childTableFirstProp: 'yet another string'}
}]
instead of this:
[{
parentTableFirstProp: 'string',
childTableFirstProp: 'another string',
},{
parentTableFirstProp: 'string',
childTableFirstProp: 'yet another string'
}]
Do I always have to make 2 select queries, and insert one to another by usage of aliases? Could you just show an example: how do you SELECT
parent table along with it's children?
UPD 1 this:
SELECT
"public"."ParentTable".*,
"public"."ChildTable".*
FROM
"public"."ParentTable"
RIGHT JOIN "public"."ChildTable"
ON "public"."ParentTable"."childReference"
returns this:
[{
parentTableFirstProp: 'string',
childTableFirstProp: 'another string',
},{
parentTableFirstProp: 'string',
childTableFirstProp: 'yet another string'
}]
UPD 2
Create tables statements:
CREATE TABLE "public"."ParentTable" (
"id" varchar(36) NOT NULL COLLATE "default",
"parentTableFirstProp" varchar(100) NOT NULL COLLATE "default",
"parentToChildReference" varchar COLLATE "default"
)
CREATE TABLE "public"."ChildTable" (
"id" varchar(36) NOT NULL COLLATE "default"
"childTableFirstProp" varchar(100) NOT NULL COLLATE "default",
)
A new feature in PostgreSQL 9.2 but I didn't test the query:
I follow the tutorial from here .
select row_to_json(t)
from (
select ParentTable.parentTableFirstProp, (
select array_to_json(array_agg(row_to_json(child)))
from (
select childTableFirstProp
from ChildTable
where ChildTable.id=ParentTable.parentToChildReference
) child
) as parentToChildReference
from ParentTable
) t
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