The only permitted root element of a query, the SELECT element The SELECT part of a query Represents the TOP and OFFSET part of a query List of items to be selected in the Query The base type for any of items to be selected in a query Represents the From part of the query The base type for all tables used in the From clause of the query Represents the Where part of the query The base type for searches in Where and Having clauses of the query Used to select an expression as a new alias column Represent all columns as in Select * query The base type for a scalar expression Represents an expression inside a bracket such as (a) Represents a binary expression such as a+b Represents an unary expression such as -(a.ra) Represents a column. Table attribute represents a table alias name. The base type for all literals Represent a function Represents an aggregate function The base type for all numbers Represents a real number Represents an integer Represents a literal of non-number type, such as string, timestamp, boolean and so on Represents a table with its archive name (optioanl), its name (required) and its alias name (required) Represents expressions like A And B Represents expressions like A Or B The Like expression of a query Represents expressions like (A) Represents the Comparison of two expressions Represents the Between expression of a query Represents the Regions such as circle in Where clause The base type for a boolean function Represents SQL IN expression The base type for selection set in a SQL IN expression Represents a list of constants provided for a SQL IN expression