The query SELECT * FROM logs WHERE info ?& ARRAY['error', 'timestamp']; returns no rows, but you expect some. What could be the problem?

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PostgreSQL - JSON and JSONB

The query SELECT * FROM logs WHERE info ?& ARRAY['error', 'timestamp']; returns no rows, but you expect some. What could be the problem?

AThe ARRAY syntax is invalid for ?& operator

BThe ?& operator checks if all keys exist; some rows may have only one key

CThe info column is not JSONB type

DThe keys should be comma-separated strings, not an array

Step-by-Step Solution

Solution:

Step 1: Understand the ?& operator
The ?& operator checks if all keys in the array exist in the JSONB column.
Step 2: Analyze why no rows are returned
If some rows have only one of the keys, they won't match because all keys must be present.
Final Answer:
The ?& operator checks if all keys exist; some rows may have only one key -> Option B
Quick Check:
?& requires all keys present [OK]

Quick Trick: ?& operator requires all keys to exist [OK]

Common Mistakes:

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