50 lines
1.2 KiB
Markdown
50 lines
1.2 KiB
Markdown
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---
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title: Write Efficient Queries
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impact: HIGH
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impactDescription: Proper filtering reduces query time by orders of magnitude
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tags: rqe, ft.search, query, performance, filters
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description: Write Efficient Queries
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alwaysApply: true
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---
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## Write Efficient Queries
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Be specific and use filters to reduce the result set early.
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**Correct:** Use specific filters and limit results.
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```
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# Good: Specific query with filters
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FT.SEARCH idx:products "@category:{electronics} @price:[100 500]"
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LIMIT 0 20
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RETURN 3 name price category
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# Good: Use SORTBY and LIMIT
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FT.SEARCH idx:products "@name:laptop"
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SORTBY price ASC
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LIMIT 0 10
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```
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**Incorrect:** Broad queries returning large result sets.
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```
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# Bad: Wildcard prefix scans entire index
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FT.SEARCH idx:products "*" LIMIT 0 10000
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# Bad: Loading all fields from source document
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FT.AGGREGATE idx:products "*" LOAD *
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```
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**Performance tips:**
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- Add `SORTABLE` to fields used in `SORTBY`
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- Use `TAG SORTABLE UNF` for best performance on tag fields
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- Use `NOSTEM` if you don't need stemming
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- Profile queries with `FT.PROFILE`
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```
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FT.PROFILE idx:products SEARCH QUERY "@category:{electronics}"
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```
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Reference: [Redis Search Query Syntax](https://redis.io/docs/latest/develop/interact/search-and-query/query/)
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