Apex Record Clone Patterns

Apex Record Clone Patterns

Activate when duplicating an sObject record in Apex — one record with a new Id, a record with its children, or a snapshot with preserved audit fields. The SObject.clone() method has four boolean flags that control deep-vs-shallow, Id preservation, readonly-field behavior, and autonumber handling. Each has failure modes if misread.

Before Starting

• Define scope. Just the record, or the record + children? Clone does NOT walk relationships by default.
• Decide Id preservation. Cloning for insert → preserveId=false (default). Cloning for in-memory work → preserveId=true.
• Audit-field expectations. CreatedDate, LastModifiedDate, etc. are readonly; preserveReadonly=true requires CreateAuditFields user permission.

Core Concepts

Method signature

public SObject clone(Boolean preserveId, Boolean isDeepClone, Boolean preserveReadonly, Boolean preserveAutonumber)

All four default to false. Typical invocations:

Account copy = acc.clone();                       // shallow, no Id, no readonly, new autonumber
Account copy = acc.clone(false, false, false, true);  // preserve autonumber
Account copy = acc.clone(true);                   // keep Id (for in-memory diffing)

Flags in detail

"Deep clone" does NOT clone children

isDeepClone=true is a misnomer — it preserves formula/aggregate field values in the in-memory copy. It does NOT fetch and clone child records.

Cloning children requires explicit query + reparent

Opportunity opp = [SELECT Id, Name, (SELECT Id, Product2Id, Quantity, UnitPrice FROM OpportunityLineItems) FROM Opportunity WHERE Id = :srcId];
Opportunity newOpp = opp.clone(false, false, false, false);
newOpp.Name = 'Copy of ' + opp.Name;
insert newOpp;
List<OpportunityLineItem> newLines = new List<OpportunityLineItem>();
for (OpportunityLineItem oli : opp.OpportunityLineItems) {
    OpportunityLineItem copy = oli.clone();
    copy.OpportunityId = newOpp.Id;
    newLines.add(copy);
}
insert newLines;

Readonly-field preservation

Account a = [SELECT Id, Name, CreatedDate FROM Account WHERE Id = :id];
Account copy = a.clone(false, false, true, false);
insert copy;  // CreatedDate preserved — only if running user has CreateAuditFields permission

Perm gate: Setup → System Permissions → "Set Audit Fields upon Record Creation" must be enabled and permission assigned.

Common Patterns

Pattern: "Copy of" with new autonumber

Case c = [SELECT Id, Subject, Origin FROM Case WHERE Id = :id];
Case copy = c.clone();            // CaseNumber autonumber regenerated
copy.Subject = 'Copy of ' + c.Subject;
insert copy;

Pattern: Deep copy of Opportunity with line items

(See "Cloning children" code above.)

Pattern: Bulk clone 1→N

List<Account> src = [SELECT Id, Name FROM Account WHERE ...];
List<Account> copies = new List<Account>();
for (Account a : src) {
    for (Integer i = 0; i < 5; i++) {
        Account c = a.clone();
        c.Name = a.Name + ' v' + i;
        copies.add(c);
    }
}
insert copies;

Pattern: Clone via Database.insert with duplicate-rule bypass

Database.DMLOptions dmo = new Database.DMLOptions();
dmo.DuplicateRuleHeader.AllowSave = true;
List<Database.SaveResult> srs = Database.insert(copies, dmo);

Decision Guidance

Recommended Workflow

1. Identify whether children need to travel. If yes, query the subselect in the source SOQL.
2. Clone the parent with the flags you need (usually clone() is sufficient).
3. Insert the parent first to obtain the new Id.
4. Clone each child, set the foreign key to the new parent Id, insert in bulk.
5. For audit-field preservation, verify the running user has CreateAuditFields.
6. Test with duplicate rules enabled AND disabled.
7. Document the clone's semantic relationship to the source (e.g., store a Cloned_From__c lookup for traceability).

Review Checklist

• Child records explicitly queried + reparented (clone does NOT do this)
• Autonumber preservation decision intentional
• Audit-field preservation paired with CreateAuditFields permission
• Bulk clone keeps DML inside limits
• Clone traceability (e.g., source-record lookup) persisted
• Duplicate rule behavior considered

Salesforce-Specific Gotchas

1. clone() does NOT recursively clone children. isDeepClone=true preserves formula values but doesn't fetch relationships.
2. preserveId=true followed by insert throws — you cannot insert with an Id. Only useful for in-memory diffing/asserting.
3. preserveReadonly=true without CreateAuditFields silently ignores audit fields — the new record gets SYSTEM.now() timestamps, not the originals.
4. OpportunityLineItem clone requires a Price Book Entry that exists on the target Opportunity — cloning across pricebooks needs repointing.
5. Record Type Id is not cleared by clone — ensure target record type is valid for the cloned picklist values.

Output Artifacts

Related Skills

• apex/apex-record-relationships — relationship traversal for deep copies
• data/bulk-api-and-large-data-loads — volume cloning via ETL
• data/external-id-strategy — matching source/target across orgs