Unverified50% confidenceFactExact time
PostgreSQL's aggregate functions ignore NULL values: COUNT(*) counts all rows, while COUNT(val), SUM, and AVG ignore NULL values.
1
Sources
50%
Confidence
Long-term
Relevance
9/12/2026
First Seen
Sources
Related Entities
Related Claims
UnverifiedPostgreSQL treats NULL as the largest value by default, placing it at the end in ascending order and at the beginning in descending order.74% similarUnverifiedIn PostgreSQL, SELECT NULL = NULL returns NULL rather than TRUE.73% similarUnverifiedDECIMAL and NUMERIC are semantically equivalent in standard SQL, both storing numbers precisely in decimal form to avoid the rounding errors of FLOAT/DOUBLE binary floating-point representation.68% similarUnverifiedUsing the wrong JOIN key in a one-to-many relationship causes row multiplication, making SUM aggregation results grow by multiples, while SQL does not throw any exception63% similar
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