Retrieving sub-fields from parsed JSON in snowflake - json

Question

I'm having some difficulty getting the individual components of the address component
with data as (select
PARSE_JSON('{ "data" : [
[ "row-ea6u~fkaa~32ry", "00000000-0000-0000-01B7-0B8F94EE5292", 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
)
select f.value[1][0]::text
from data d,
lateral flatten(input=> d.j:data,recursive=>TRUE) f;
f.value[1][0] has a field address
{"address": "4509 BELAIR ROAD", "city": "Baltimore", "state": "MD", "zip": ""}
but
f.value[1][0].address returns null
How do I get the individual attributes of f.value[1] like address, city, etc?

Answer 1

The problem is given you have three levels of nested data, you should not be using recursive=>TRUE as the objects are not the same, so you cannot make anything of value out of the data. You need to break the different layers apart manually.
with data as (
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
), data_rows as (
select f.value as r
from data d,
lateral flatten(input=> d.j:data) f
)
select dr.r[0] as v0
,dr.r[1] as v1
,dr.r[2] as v2
,dr.r[3] as v3
,f.value as addr_n
from data_rows dr,
lateral flatten(input=> dr.r[13]) f;
so this get all the rows (of which your example has only one) the unpacks the values of interest (you will need to complete this part and give v0 - vN meaning) but there is an array or addresses
V0 V1 V2 V3 ADDR_N
"row-ea6u~fkaa~32ry" "0B8F94EE5292" 0 1486063689 "{\"address\": \"4509 BELAIR ROAD\", \"city\": \"Baltimore\", \"state\": \"MD\", \"zip\": \"\"}"
"row-ea6u~fkaa~32ry" "0B8F94EE5292" 0 1486063689 null
"row-ea6u~fkaa~32ry" "0B8F94EE5292" 0 1486063689 null
"row-ea6u~fkaa~32ry" "0B8F94EE5292" 0 1486063689 null
"row-ea6u~fkaa~32ry" "0B8F94EE5292" 0 1486063689 true
now to decode the address as json ,parse_json(f.value) as addr_n does that, so you can break it apart like:
with data as (
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
), data_rows as (
select f.value as r
from data d,
lateral flatten(input=> d.j:data) f
)
select dr.r[0] as v0
,dr.r[1] as v1
,dr.r[2] as v2
,dr.r[3] as v3
,parse_json(f.value) as addr_n
,addr_n:address::text as addr_address
,addr_n:city::text as addr_city
,addr_n:state::text as addr_state
,addr_n:zip::text as addr_zip
from data_rows dr,
lateral flatten(input=> dr.r[13]) f;
you can ether leave the addr_n dummy variable or swap it out by cut'n'pasting it like so:
,parse_json(f.value):address::text as addr_address
,parse_json(f.value):city::text as addr_city
,parse_json(f.value):state::text as addr_state
,parse_json(f.value):zip::text as addr_zip

Answer 2

You can follow the article for step-by-step for achieving it:
https://community.snowflake.com/s/article/Using-lateral-flatten-to-extract-data-from-JSON-internal-field
Hope this helps!