where() public method Sets the WHERE part of the query

one() public method Executes the query and returns a single

orHaving() public method Adds an additional HAVING condition

leftJoin() public method Appends a LEFT OUTER JOIN part

$union public property This is used to construct the UNION clause(s)

createCommand() public method Creates a DB command that

orWhere() public method Adds an additional WHERE condition

queryScalar() protected method Queries a scalar value

addGroupBy() public method Adds additional group-by columns

create() public static method Creates a new Query object