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SQL

SQL: Use COALESCE to Handle NULL Values

- 19.03.26 | 19.03.26 - ErcanOPAK

NULL values breaking calculations? Use COALESCE for fallback.

-- Returns first non-NULL value
SELECT COALESCE(Phone, Email, 'No contact') AS Contact
FROM Users;

-- Default values in calculations
SELECT 
  Name,
  Price * COALESCE(Quantity, 0) AS Total
FROM Orders;

-- Multiple fallbacks
SELECT COALESCE(PreferredName, FirstName, 'Unknown') AS DisplayName
FROM Users;

vs ISNULL: COALESCE is ANSI standard (works everywhere). ISNULL is SQL Server only.

vs CASE: Shorter, cleaner syntax.

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Post Views: 10

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