You designed a DynamoDB table with primary key { PartitionKey: 'UserId' } but your app needs to query orders by OrderDate. What is the main problem and how to fix it?
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DynamoDB - Access Patterns and Query Optimization
You designed a DynamoDB table with primary key { PartitionKey: 'UserId' } but your app needs to query orders by OrderDate. What is the main problem and how to fix it?
AProblem: Table size is too big; Fix: Use smaller partition keys
BProblem: Cannot query by OrderDate efficiently; Fix: Add OrderDate as sort key
CProblem: UserId is missing; Fix: Add UserId as partition key
DProblem: Query syntax error; Fix: Use Scan instead of Query
Step-by-Step Solution
Solution:
Step 1: Identify the limitation of current key design
With only partition key UserId, you cannot efficiently query by OrderDate alone.
Step 2: Suggest design fix for access pattern
Adding OrderDate as sort key allows queries by UserId and ordered by OrderDate efficiently.
Final Answer:
Problem: Cannot query by OrderDate efficiently; Fix: Add OrderDate as sort key -> Option B
Quick Check:
Sort key enables range queries by date [OK]
Quick Trick:Add sort key for secondary query attribute [OK]
Common Mistakes:
MISTAKES
Trying to query by non-key attribute without index
Using Scan instead of fixing key design
Ignoring need for composite key for multiple access patterns
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