Common Salesforce Apex Errors & Solutions

 Apex development comes with its own set of challenges. Here are some frequent errors you may encounter, along with practical solutions to help you debug and resolve them quickly.

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1. SOQL Query Limit Exceeded

Error:

System.LimitException: Too many SOQL queries: 101

Solution:

• Bulkify your code—avoid SOQL queries inside loops.
• Consolidate queries and retrieve related data in one go.

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2. CPU Time Limit Exceeded

Error:

System.LimitException: Apex CPU time limit exceeded

Solution:

• Optimize logic and avoid unnecessary looping.
• Use efficient collections (Map, Set).
• Move long-running tasks to asynchronous processes (Batch, Queueable).

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3. DML Statement Limit Exceeded

Error:

System.LimitException: Too many DML statements: 151

Solution:

• Perform DML operations in bulk, not one-by-one.
• Minimize updates/inserts inside loops.

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4. Attempt to de-reference a null object

Error:

System.NullPointerException: Attempt to de-reference a null object

Solution:

• Check for null before accessing object fields or methods.
• Use safe navigation (?.) operator where possible.

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5. Mixed DML Operation Error

Error:

System.DmlException: DML operation on setup object is not permitted after you have performed DML on non-setup object

Solution:

• Separate DML operations for setup (User, Profile, etc.) and non-setup objects in different transactions.
• Use @future methods for setup object DML after non-setup DML.

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6. FIELD_INTEGRITY_EXCEPTION

Error:

FIELD_INTEGRITY_EXCEPTION, field is not writeable

Solution:

• Check Field Level Security (FLS) and object permissions.
• Ensure the field is editable for the running user.

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7. Too Many Uncommitted Work Pending Errors

Error:

System.UnexpectedException: Too many uncommitted work pending

Solution:

• Avoid multiple callouts, DML, or email sends in the same transaction.
• Refactor logic into asynchronous methods if needed.

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8. Recursive Trigger Error

Error:

Maximum trigger depth exceeded

Solution:

• Implement static variables or custom logic to prevent recursion.
• Always check for context before updating records in triggers.

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9. UNABLE_TO_LOCK_ROW

Error:

UNABLE_TO_LOCK_ROW, unable to obtain exclusive access to this record

Solution:

• Use FOR UPDATE in SOQL for record locking.
• Review and avoid simultaneous updates to the same records.

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10. Malformed Query/Invalid Field

Error:

System.QueryException: No such column 'FieldName' on entity 'ObjectName'

Solution:

• Double-check field and object API names.
• Use Schema Explorer or describe calls to validate fields.

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Pro Tip:
Always use meaningful exception handling and logging to make error diagnosis easier!