Parsing JSON without key names to retrieve a column - json

Question

I am loading json from data.gov that does not have key names for the values in the json data, e.g. below: the metadata is available separately.
I am able to load the json into a variant column, but cannot see how to parse and query for specific columns, e.g. Frankford below - I have tried JSONcol:data[0] which returns the entire entry, but am unable to see how to specify column 4, say.
{
data: [ [ "row-ea6u~fkaa~32ry", "0B8F94EE5292", 0, 1486063689, null, 1486063689, null, "{ }", "410", "21206", "Frankford", "2", "NORTHEASTERN", [ "{\"address\": \"4509 BELAIR ROAD\", \"city\": \"Baltimore\", \"state\": \"MD\", \"zip\": \"\"}", null, null, null, true ], null, null, null ]]
}
The following code is used to create and load the snowflake table:
create or replace table snowpipe.public.snowtable(jsontext variant);
copy into snowpipe.public.snowtable
from #snowpipe.public.snowstage
file_format = (type = 'JSON')

Answer 1

Not exactly sure how your varient data is look once you have loaded it, but experimenting on variant via PARSE_JSON for you object. Which I has to double slash the \ to make it valid sql.
select
PARSE_JSON('{ data: [ [ "row-ea6u~fkaa~32ry", "0B8F94EE5292", 0, 1486063689, null, 1486063689, null, "{ }", "410", "21206", "Frankford", "2", "NORTHEASTERN", [ "{\\"address\\": \\"4509 BELAIR ROAD\\", \\"city\\": \\"Baltimore\\", \\"state\\": \\"MD\\", \\"zip\\": \\"\\"}", null, null, null, true ], null, null, null ]]}') as j
,j:data as jd
,jd[0] as jd0
,jd0[3] as jd0_3
,array_slice(j:data[0],3,5) as jd0_3to4
;
shows that you can use [0] notation to index arrays, and thus get the results:
J: { "data": [ [ "row-ea6u~fkaa~32ry", "0B8F94EE5292", 0, 1486063689, null, 1486063689, null, "{ }", "410", "21206", "Frankford", "2", "NORTHEASTERN", [ "{\"a...
JD: [ [ "row-ea6u~fkaa~32ry", "0B8F94EE5292", 0, 1486063689, null, 1486063689, null, "{ }", "410", "21206", "Frankford", "2", "NORTHEASTERN", [ "{\"address\": \"4509 BELAIR ROAD\", \"city\": \"...
JD0: [ "row-ea6u~fkaa~32ry", "0B8F94EE5292", 0, 1486063689, null, 1486063689, null, "{ }", "410", "21206", "Frankford", "2", "NORTHEASTERN", [ "{\"address\": \"4509 BELAIR ROAD\", \"city\": \"Baltimore\", \"state\": \"MD\", \"...
JD0_3: 1486063689
JD0_3TO4: [ 1486063689, null ]
so if you have unknown amount of first level elements in data that you want to access, then use LATERAL FLATTEN like so:
WITH data as (
select PARSE_JSON('{ data: [ [ "row-1", "0B8", 0 ],["row-2", "F94", 2],
["row-3", "EE5", 4]]}') as j
)
select f.value[0]::text as row_name
,f.value[1]::text as serial_number
,f.value[2]::number as num
from data d,
lateral flatten(input=> d.j:data) f;
gives:
ROW_NAME SERIAL_NUMBER NUM
row-1 0B8 0
row-2 F94 2
row-3 EE5 4