SQL WHERE col IN (...)
with Numerous Values: Performance and Limitations
Using the SQL WHERE col IN (...)
clause with a large number of values can lead to performance issues. Database systems impose limits on the size of the IN
list, and exceeding these limits can cause query failures. The specific limit varies greatly depending on the database system.
While Microsoft SQL Server boasts a high limit (details available at https://www.php.cn/link/a6ed9258d53b17bac9cfd263432af8fa), other systems, like Oracle, may encounter limitations more readily.
To avoid these issues and improve query performance, especially with extensive IN
lists, it's best practice to utilize a temporary table. Populate this temporary table with your values and then perform a JOIN
operation. This approach generally outperforms a long IN
clause.
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