org.eigenbase.sql.fun
Class SqlCursorConstructor

java.lang.Object
  org.eigenbase.sql.SqlOperator
      org.eigenbase.sql.SqlSpecialOperator
          org.eigenbase.sql.fun.SqlCursorConstructor

public class SqlCursorConstructor
extends SqlSpecialOperator

SqlCursorConstructor defines the non-standard CURSOR(<query>) constructor.

Version:

$Id: //open/dev/farrago/src/org/eigenbase/sql/fun/SqlCursorConstructor.java#11 $

Author:

John V. Sichi

Field Summary

Fields inherited from class org.eigenbase.sql.SqlOperator

MaxPrec, NL

Constructor Summary

SqlCursorConstructor()

Method Summary

boolean	argumentMustBeScalar(int ordinal) Returns whether the ordinalth argument to this operator must be scalar (as opposed to a query).
RelDataType	deriveType(SqlValidator validator, SqlValidatorScope scope, SqlCall call) Derives the type of a call to this operator.
void	unparse(SqlWriter writer, SqlNode[] operands, int leftPrec, int rightPrec) Writes a SQL representation of a call to this operator to a writer, including parentheses if the operators on either side are of greater precedence.

Methods inherited from class org.eigenbase.sql.SqlSpecialOperator

getSyntax, reduceExpr

Methods inherited from class org.eigenbase.sql.SqlOperator

acceptCall, acceptCall, adjustType, checkOperandCount, checkOperandTypes, createCall, createCall, createCall, createCall, equals, getAllowedSignatures, getAllowedSignatures, getKind, getLeftPrec, getMonotonicity, getName, getOperandCountRange, getOperandTypeChecker, getOperandTypeInference, getReturnTypeInference, getRightPrec, getSignatureTemplate, hashCode, inferReturnType, inferReturnType, isAggregator, isDeterministic, isDynamicFunction, isName, leftPrec, preValidateCall, requiresDecimalExpansion, rewriteCall, rightPrec, toString, unparseListClause, unparseListClause, validateCall, validateOperands

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SqlCursorConstructor

public SqlCursorConstructor()

Method Detail

deriveType

public RelDataType deriveType(SqlValidator validator,
                              SqlValidatorScope scope,
                              SqlCall call)

Description copied from class: SqlOperator

Derives the type of a call to this operator.

This method is an intrinsic part of the validation process so, unlike SqlOperator.inferReturnType(org.eigenbase.sql.SqlOperatorBinding), specific operators would not typically override this method.

Overrides:

deriveType in class SqlOperator

Parameters:

validator - Validator

scope - Scope of validation

call - Call to this operator

Returns:

Type of call

unparse

public void unparse(SqlWriter writer,
                    SqlNode[] operands,
                    int leftPrec,
                    int rightPrec)

Description copied from class: SqlOperator

Writes a SQL representation of a call to this operator to a writer, including parentheses if the operators on either side are of greater precedence.

The default implementation of this method delegates to SqlSyntax.unparse(org.eigenbase.sql.SqlWriter, org.eigenbase.sql.SqlOperator, org.eigenbase.sql.SqlNode[], int, int).

Overrides:

unparse in class SqlSpecialOperator

argumentMustBeScalar

public boolean argumentMustBeScalar(int ordinal)

Description copied from class: SqlOperator

Returns whether the ordinalth argument to this operator must be scalar (as opposed to a query).

If true (the default), the validator will attempt to convert the argument into a scalar subquery, which must have one column and return at most one row.

Operators such as SELECT and EXISTS override this method.

Overrides:

argumentMustBeScalar in class SqlOperator