30 lines
935 B
Markdown
30 lines
935 B
Markdown
# Storage Warnings
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Storage sometimes logs warnings to stderr. This page explains the cause and
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possible solutions for these warnings.
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## Sort Operations
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The warning message will say something like:
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```
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Suboptimal indexes for the SQL statement `<sql>` [<n> sort operation(s)]
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```
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This happens when you have an `ORDER BY` clause that does not use an index.
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When no index is used, all results from the query must be fetched first and then
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sorted. When an index is used, data can be obtained row by row from the
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database, which is much faster.
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If you cannot use an index in your `ORDER BY` clause, you can suppress this
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warning by including a SQL comment in your query that contains the text:
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```
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/* do not warn (bug XXXXXXX) */
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```
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The bug number referenced should explain why the query cannot use an index.
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The printed SQL is the prepared statement text, so bound parameters appear as
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`?` placeholders rather than their values.
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