org.apache.calcite.sql

Class SqlOperatorBinding

java.lang.Object

org.apache.calcite.sql.SqlOperatorBinding

Direct Known Subclasses:

Aggregate.AggCallBinding, ExplicitOperatorBinding, RexCallBinding, SqlCallBinding

public abstract class SqlOperatorBinding
extends Object

SqlOperatorBinding represents the binding of an SqlOperator to actual operands, along with any additional information required to validate those operands if needed.

Field Summary

Fields

Modifier and Type	Field and Description
protected RelDataTypeFactory	typeFactory

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SqlOperatorBinding(RelDataTypeFactory typeFactory, SqlOperator sqlOperator) Creates a SqlOperatorBinding.

Method Summary

Methods

Modifier and Type	Method and Description
List<RelDataType>	collectOperandTypes() Collects the types of the bound operands into a list.
String	getColumnListParamInfo(int ordinal, String paramName, List<String> columnList) Retrieves information about a column list parameter.
RelDataType	getCursorOperand(int ordinal) Returns the rowtype of the ordinalth operand, which is a cursor.
int	getGroupCount() If the operator call occurs in an aggregate query, returns the number of columns in the GROUP BY clause.
int	getIntLiteralOperand(int ordinal) Gets the integer value of a numeric literal operand.
abstract int	getOperandCount()
abstract RelDataType	getOperandType(int ordinal) Gets the type of a bound operand.
SqlOperator	getOperator()
String	getStringLiteralOperand(int ordinal) Gets the string value of a string literal operand.
RelDataTypeFactory	getTypeFactory()
boolean	isOperandNull(int ordinal, boolean allowCast) Determines whether a bound operand is NULL.
abstract CalciteException	newError(Resources.ExInst<SqlValidatorException> e) Wraps a validation error with context appropriate to this operator call.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

typeFactory

protected final RelDataTypeFactory typeFactory

Constructor Detail

SqlOperatorBinding

protected SqlOperatorBinding(RelDataTypeFactory typeFactory,
                  SqlOperator sqlOperator)

Creates a SqlOperatorBinding.

Parameters:

typeFactory - Type factory

sqlOperator - Operator which is subject of this call

Method Detail

getGroupCount

public int getGroupCount()

If the operator call occurs in an aggregate query, returns the number of columns in the GROUP BY clause. For example, for "SELECT count(*) FROM emp GROUP BY deptno, gender", returns 2.

Returns 0 if the query is implicitly "GROUP BY ()" because of an aggregate expression. For example, "SELECT sum(sal) FROM emp".

Returns -1 if the query is not an aggregate query.

getOperator

public SqlOperator getOperator()

Returns:

bound operator

getTypeFactory

public RelDataTypeFactory getTypeFactory()

Returns:

factory for type creation

getStringLiteralOperand

public String getStringLiteralOperand(int ordinal)

Gets the string value of a string literal operand.

Parameters:

ordinal - zero-based ordinal of operand of interest

Returns:

string value

getIntLiteralOperand

public int getIntLiteralOperand(int ordinal)

Gets the integer value of a numeric literal operand.

Parameters:

ordinal - zero-based ordinal of operand of interest

Returns:

integer value

isOperandNull

public boolean isOperandNull(int ordinal,
                    boolean allowCast)

Determines whether a bound operand is NULL.

This is only relevant for SQL validation.

Parameters:

ordinal - zero-based ordinal of operand of interest

allowCast - whether to regard CAST(constant) as a constant

Returns:

whether operand is null; false for everything except SQL validation

getOperandCount

public abstract int getOperandCount()

Returns:

the number of bound operands

getOperandType

public abstract RelDataType getOperandType(int ordinal)

Gets the type of a bound operand.

Parameters:

ordinal - zero-based ordinal of operand of interest

Returns:

bound operand type

collectOperandTypes

public List<RelDataType> collectOperandTypes()

Collects the types of the bound operands into a list.

Returns:

collected list

getCursorOperand

public RelDataType getCursorOperand(int ordinal)

Returns the rowtype of the ordinalth operand, which is a cursor.

This is only implemented for SqlCallBinding.

Parameters:

ordinal - Ordinal of the operand

Returns:

Rowtype of the query underlying the cursor

getColumnListParamInfo

public String getColumnListParamInfo(int ordinal,
                            String paramName,
                            List<String> columnList)

Retrieves information about a column list parameter.

Parameters:

ordinal - ordinal position of the column list parameter

paramName - name of the column list parameter

columnList - returns a list of the column names that are referenced in the column list parameter

Returns:

the name of the parent cursor referenced by the column list parameter if it is a column list parameter; otherwise, null is returned

newError

public abstract CalciteException newError(Resources.ExInst<SqlValidatorException> e)

Wraps a validation error with context appropriate to this operator call.

Parameters:

e - Validation error, not null

Returns:

Error wrapped, if possible, with positional information