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SQL

Why COUNT(*) Can Be Slow on Large Tables

- 25.01.26 - ErcanOPAK

Counting rows forces full scans.

SELECT COUNT_BIG(*) FROM Orders WITH (NOLOCK);

Why this matters
On massive tables, counts are expensive — cache or approximate when possible.

Related posts:

SQL: Use STRING_AGG to Concatenate Rows into Comma-Separated List

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Post Views: 9

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