Unable to access data in Postgres query where clause - sql

Question

I am dealing with the following JSON in a Postgres database column called steps in a table called tCampaign :
[
{
"name":"Step 1",
"stepReference":"01e9f7c0-bc79-11eb-ab6f-2fa1cb676e38",
"rewardConditions": [
{
"conditionDefinitions": [
{
"instanceId":"01805260-0818-4e99-e5b1-5820d1b133cd",
"type":"registration",
"properties": null,
"name": "Registration"
},
{
"instanceId":"01e115c3-5e56-437a-5d13-6c04281e9588",
"type":"optIn",
"properties": null,
"name":"Opt In"
}
],
"rewardDefinitions":[
{
"instanceId":"01c82190-1d56-44f9-474a-513732302e28",
"type":"sportsReward",
"properties": {"activation": {"type": "onReward"}, "betFlavour": "SPORTS", "channels": ["__use_campaign_restrictions__"], "expiry": {"offset": {"days": "02", "hours": "00", "minutes": "00", "seconds": "00"}, "type": "relative"}, "inRunning": "-", "maxReward": {"USD": "1"}, "minimumOdds": "", "oddsInput": {"minimumOdds": {"american": "", "european": ""}}, "retail": "offBetBuild", "returnStakeOnPayout": "false"},
"name":"Freebet",
"calculator":{"type":"fixed","value":"100"}
}
]
}
]
},
{
"name" : "Step 2",
"stepReference" : "01daa4a0-bc79-11eb-ab6f-2fa1cb676e38",
"rewardConditions": [
{
"conditionDefinitions": [
{
"instanceId" : "01fb15ae-01d0-49e1-966a-8ff438e9a191",
"type" : "genericSportsBet",
"properties" : {"betFlavour": "SPORTS", "betTrackEventThreshold": "10", "betTypes": [ "SGL" ], "builderBetOption": "ALL", "channels": [ "__use_campaign_restrictions__" ], "currencyThresholdMap": { "USD": "1" }, "eventHierarchySelection": { "categories": [], "classes": [], "events": [], "marketTemplates": [], "markets": [ "5824" ], "retrobetEventIds": [ "1200" ], "selections": [], "selectionsMarket": [], "types": [] }, "eventHierarchySelectionUI": { "markets": [ { "id": 5824, "mapping": [], "name": "Match Result", "parentId": 1200, "parentParentId": 5, "path": [ "Category: |England|", "Class: |England Premier League|", "Type: |GK Team K| |vs| |GK Team L|" ], "selectionMapper": false, "settled": "N", "startTime": "2021-05-31 11:15:00", "status": "A" } ] }, "inRunning": "-", "legTypes": [ "WIN" ], "metOnSettlement": false, "minOdds": "", "oddsInput": { "minOdds": { "american": "", "european": "" } }, "priceTypes": [ "LP" ]},
"name" : "Sports Bet"
}
],
"rewardDefinitions":[
{
"instanceId" : "0110eb70-44f9-4d57-40bb-09ff4169136c",
"type" : "sportsReward",
"properties" : {"activation": {"type": "onReward"}, "betFlavour": "SPORTS", "channels": ["__use_campaign_restrictions__"], "expiry": {"offset": {"days": "02", "hours": "00", "minutes": "00", "seconds": "00"}, "type": "relative"}, "inRunning": "-", "maxReward": {"USD": "2"}, "minimumOdds": "", "oddsInput": {"minimumOdds": {"american": "", "european": ""}}, "retail": "offBetBuild", "returnStakeOnPayout": "false"},
"name" : "Freebet",
"calculator" : {"type":"fixed","value":"100"}
}
]
}
]
}
]
and have written the following query to extract properties from conditionDefinitions :
select conditionDefinitions->'properties' as properties from tcampaign cmp
LEFT JOIN LATERAL json_array_elements(steps) singleStep ON true
LEFT JOIN LATERAL json_array_elements(singleStep->'rewardConditions') rewardConditions on TRUE
LEFT JOIN LATERAL json_array_elements(rewardConditions->'conditionDefinitions') conditionDefinitions on TRUE
where properties is not null ;
but I get the following error :
ERROR: column "properties" does not exist
LINE 5: where properties is null ;
If I remove the where clause the query runs fine. Why do I not have access to properties in the where clause? Because I can see results coming back if I remove the WHERE clause, so the query does have results