Subquery Guide

addSubquery

Add a subquery to the query, selecting an SObject list from a specific child relationship.

For example, in this query, the expression enclosed in parentheses is a subquery:

SELECT Name, (SELECT LastName FROM Contacts) FROM Account

public Query addSubquery(String relationshipName)

relationshipName: Name of the child relationship

Query q =
    new Query('Account').
    addSubquery('Contacts');

public Query addSubquery(String relationshipName, String fields)

relationshipName: Name of the child relationship

fields: One or more field names in the child relationship that will be selected. If there are more than one field, they will be separated by a comma ','.

Query q =
    new Query('Account').
    addSubquery('Contacts', 'FirstName, LastName').
    addSubquery('Notes', 'Title');

public Query addSubquery(String relationshipName, Set fieldSet)

relationshipName: Name of the child relationship

fieldSet: A set of field names in the child relationship that will be selected

Query q =
    new Query('Account').
    addSubquery('Contacts', new Set{'FirstName', 'LastName'});

public Query addSubquery(String relationshipName, List fieldList)

relationshipName: Name of the child relationship

fieldList: A list of field names in the child relationship that will be selected

Query q =
    new Query('Account').
    addSubquery('Contacts', new List{'FirstName', 'LastName'});

public Query addSubquery(Query subquery)

subquery: A subquery instance constructed by the static methodQuery.subquery

Query q =
    new Query('Account').
    addSubquery(Query.subquery('Contacts'));

subquery

Creates a subquery instance.

The instance can be linked to the main query using the addSubquery method afterwards.

public static Query subquery(String relationshipName)

relationshipName: Name of the child relationship

Query q =
    new Query('Account').
    addSubquery(Query.subquery('Contacts'));