org.apache.calcite.sql.fun

Class SqlSequenceValueOperator

java.lang.Object

org.apache.calcite.sql.SqlOperator

org.apache.calcite.sql.SqlSpecialOperator

org.apache.calcite.sql.fun.SqlSequenceValueOperator

public class SqlSequenceValueOperator
extends SqlSpecialOperator

Operator that returns the current or next value of a sequence.

Field Summary

Fields inherited from class org.apache.calcite.sql.SqlOperator

kind, MDX_PRECEDENCE, NL

Method Summary

Methods

Modifier and Type	Method and Description
RelDataType	deriveType(SqlValidator validator, SqlValidatorScope scope, SqlCall call) Derives the type of a call to this operator.
boolean	isDeterministic()
void	unparse(SqlWriter writer, SqlCall call, 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.
void	validateCall(SqlCall call, SqlValidator validator, SqlValidatorScope scope, SqlValidatorScope operandScope) Validates a call to this operator.

Methods inherited from class org.apache.calcite.sql.SqlSpecialOperator

getSyntax, reduceExpr

Methods inherited from class org.apache.calcite.sql.SqlOperator

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

Methods inherited from class java.lang.Object

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

Method Detail

isDeterministic

public boolean isDeterministic()

Overrides:

isDeterministic in class SqlOperator

Returns:

true iff a call to this operator is guaranteed to always return the same result given the same operands; true is assumed by default

unparse

public void unparse(SqlWriter writer,
           SqlCall call,
           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.apache.calcite.sql.SqlWriter, org.apache.calcite.sql.SqlOperator, org.apache.calcite.sql.SqlCall, int, int).

Overrides:

unparse in class SqlOperator

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.apache.calcite.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

validateCall

public void validateCall(SqlCall call,
                SqlValidator validator,
                SqlValidatorScope scope,
                SqlValidatorScope operandScope)

Description copied from class: SqlOperator

Validates a call to this operator.

This method should not perform type-derivation or perform validation related related to types. That is done later, by SqlOperator.deriveType(SqlValidator, SqlValidatorScope, SqlCall). This method should focus on structural validation.

A typical implementation of this method first validates the operands, then performs some operator-specific logic. The default implementation just validates the operands.

This method is the default implementation of SqlCall.validate(org.apache.calcite.sql.validate.SqlValidator, org.apache.calcite.sql.validate.SqlValidatorScope); but note that some sub-classes of SqlCall never call this method.

Overrides:

validateCall in class SqlOperator

Parameters:

call - the call to this operator

validator - the active validator

scope - validator scope

operandScope - validator scope in which to validate operands to this call; usually equal to scope, but not always because some operators introduce new scopes

See Also:

SqlNode.validateExpr(SqlValidator, SqlValidatorScope), SqlOperator.deriveType(SqlValidator, SqlValidatorScope, SqlCall)