更新雪花变体列中的名称

Question

I have copied some json files into Snowflake from a stage and I have a property name which contains a hyphen.

When I try to query for this property name (as shown below), I get this error.

select my_variant:test-id from mytable; 

SQL compilation error: error line 1 at position 44 invalid identifier 'ID'. 

I assume it doesn't like the hyphen. Is there any way I can rename this hyphenated name in my variant column so I don't get the error?

Answer 1

You just need to quote the column name in the variant:

select my_variant:"test-id" from mytable; 

If you want to update it, see below. It assumes that you have a key per row, so that we can aggregate it back to rebuild the variant at the row level.

Setup test table:

create or replace table test (k int, a variant);

insert into test 
select 1, parse_json('{"test-id": 1, "test-id2": "2"}')
union all
select 2, parse_json('{"test-1": 1, "test-2": "2"}');

select * from test;

+---+-------------------+
| K | A                 |
|---+-------------------|
| 1 | {                 |
|   |   "test_id": 1,   |
|   |   "test_id2": "2" |
|   | }                 |
| 2 | {                 |
|   |   "test_1": 1,    |
|   |   "test_2": "2"   |
|   | }                 |
+---+-------------------+

Update the table:

update test t
set t.a = b.value
from (
    with t as (
        select
            k,
            replace(f.key, '-', '_') as key,
            f.value as value
        from test,
        lateral flatten(a) f
    )
    select 
        k, object_agg(key, value) as value
    from t
    group by k
) b
where t.k = b.k
;

select * from test;

+---+-------------------+
| K | A                 |
|---+-------------------|
| 1 | {                 |
|   |   "test_id": 1,   |
|   |   "test_id2": "2" |
|   | }                 |
| 2 | {                 |
|   |   "test_1": 1,    |
|   |   "test_2": "2"   |
|   | }                 |
+---+-------------------+