[Solved] Given a JSONB column info with value '{"location": {"city": "Boston"}}', why does the query SELECT info #>> '{location,street}' FROM places; return NULL? | PostgreSQL

PostgreSQL - JSON and JSONB

Given a JSONB column info with value '{"location": {"city": "Boston"}}', why does the query
SELECT info #>> '{location,street}' FROM places; return NULL?

AThe operator #>> cannot be used with nested JSON paths

BThe key 'street' does not exist under 'location' in the JSON data

CThe JSON data is malformed

DThe query syntax is incorrect

Step-by-Step Solution

Solution:

Step 1: Analyze JSON structure
The JSON contains 'location' with a 'city' key, but no 'street' key.
Step 2: Understand #>> behavior
The #>> operator returns NULL if the specified path does not exist.
Final Answer:
The key 'street' does not exist under 'location' in the JSON data -> Option B
Quick Check:
Check JSON keys at path [OK]

Quick Trick: Missing JSON key causes NULL with #>> [OK]

Common Mistakes:

Assuming #>> returns empty string if key missing
Thinking #>> fails on nested paths
Ignoring JSON structure

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Given a JSONB column info with value '{"location": {"city": "Boston"}}', why does the query

Step 1: Analyze JSON structure

Step 2: Understand #>> behavior

Final Answer:

Quick Check:

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