Users complain that a page is very slow to respond. Upon investigation, the query below is found to perform slowly. Which two actions can a developer take to improve performance? (Choose two.)

A. Make the CustomField_c field an External ID.
B. Make the field CustomField_c required because Salesforce field indexes do not include nulls.
C. Add a LIMIT clause to the query to reduce the number of records returned.
D. Contact Salesforce customer support to create a custom index to include null values.

Suggest answer: AC

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