50 lines
1.4 KiB
Markdown
50 lines
1.4 KiB
Markdown
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---
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title: Use JSON Paths for Partial Updates
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impact: MEDIUM
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impactDescription: Avoids fetching and rewriting entire documents
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tags: json, partial-updates, paths, atomic
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description: Use JSON Paths for Partial Updates
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alwaysApply: true
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---
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## Use JSON Paths for Partial Updates
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Use JSON path syntax to update specific fields without fetching the entire document.
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**Correct:** Use JSON paths for targeted updates.
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```python
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# Store JSON document
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redis.json().set("user:1001", "$", {
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"name": "Alice",
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"email": "alice@example.com",
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"preferences": {"theme": "dark", "notifications": True}
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})
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# Update nested field without fetching entire document
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redis.json().set("user:1001", "$.preferences.theme", "light")
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# Get specific field
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theme = redis.json().get("user:1001", "$.preferences.theme")
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# Increment numeric field atomically
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redis.json().numincrby("user:1001", "$.preferences.volume", 5)
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# Append to array
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redis.json().arrappend("user:1001", "$.tags", "premium")
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```
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**Incorrect:** Storing JSON as a string and parsing client-side.
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```python
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# Bad: Loses queryability and atomic updates
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redis.set("user:1001", json.dumps(user_data))
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# Must fetch, parse, modify, serialize, and rewrite
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data = json.loads(redis.get("user:1001"))
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data["preferences"]["theme"] = "light"
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redis.set("user:1001", json.dumps(data))
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```
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Reference: [Redis JSON Path](https://redis.io/docs/latest/develop/data-types/json/path/)
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