SOQL and SOSL Reference

Introduction to SOQL and SOSL
Salesforce Object Query Language (SOQL)
Typographical Conventions in This Document
Quoted String Escape Sequences
Reserved Characters
Alias Notation
SOQL SELECT Syntax
SOQL SELECT Examples
SOQL SELECT Functions
Aggregate Functions
convertCurrency()
convertTimezone()
Date Functions
FORMAT ()
GROUPING( fieldName ) )
toLabel()
Relationship Queries
Change the Batch Size in Queries
SOQL Object Limits and Limitations
Syndication Feed SOQL and Mapping Syntax
Location-Based SOQL Queries
Considerations for Querying Currency Data Using SOQL
Salesforce Object Search Language (SOSL)
PDF

GROUPING( fieldName ) )

You can use the GROUPING(fieldName) function in SELECT, HAVING, and ORDER BY clauses.

Use the GROUPING(fieldName) function to determine whether a row is a subtotal or field when you use GROUP BY ROLLUP or GROUP BY CUBE in SOQL queries.

GROUPING(fieldName) returns 1 if the row is a subtotal for the field, and 0 otherwise.

1SELECT LeadSource, Rating,
2    GROUPING(LeadSource) grpLS, GROUPING(Rating) grpRating,
3    COUNT(Name) cnt
4FROM Lead
5GROUP BY ROLLUP(LeadSource, Rating)

For more details, see Identify Subtotals with GROUP BY.