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SQL

Why COUNT(*) Gets Slow on “Big Enough” Tables

- 31.01.26 - ErcanOPAK

It’s not the count.
It’s locking + metadata access.

Reality
COUNT must respect:

  • Isolation level

  • Pending writes

  • Allocation metadata

Production alternative
Use approximate counts for dashboards.

Why
Accuracy isn’t always worth blocking.

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Post Views: 4

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