Package org.apache.calcite.sql.type

Class LiteralOperandTypeChecker

  • All Implemented Interfaces:
    SqlOperandTypeChecker, SqlSingleOperandTypeChecker
    public class LiteralOperandTypeChecker
extends java.lang.Object
implements SqlSingleOperandTypeChecker
    Parameter type-checking strategy type must be a literal (whether null is allowed is determined by the constructor). CAST(NULL as ...) is considered to be a NULL literal but not CAST(CAST(NULL as ...) AS ...)

    • Field Detail

      • allowNull

        private boolean allowNull

    • Constructor Detail

      • LiteralOperandTypeChecker

        public LiteralOperandTypeChecker​(boolean allowNull)

    • Method Detail

      • checkSingleOperandType

        public boolean checkSingleOperandType​(SqlCallBinding callBinding,
                                      SqlNode node,
                                      int iFormalOperand,
                                      boolean throwOnFailure)
        Description copied from interface: SqlSingleOperandTypeChecker
        Checks the type of a single operand against a particular ordinal position within a formal operator signature. Note that the actual ordinal position of the operand being checked may be different from the position of the formal operand.

        For example, when validating the actual call 

        C(X, Y, Z)

        the strategy for validating the operand Z might involve checking its type against the formal signature OP(W). In this case, iFormalOperand would be zero, even though the position of Z within call C is two.

        Specified by:
        checkSingleOperandType in interface SqlSingleOperandTypeChecker
        Parameters:
        callBinding - description of the call being checked; this is only provided for context when throwing an exception; the implementation should NOT examine the operands of the call as part of the check
        node - the actual operand to be checked
        iFormalOperand - the 0-based formal operand ordinal
        throwOnFailure - whether to throw an exception if check fails (otherwise returns false in that case)
        Returns:
        whether check succeeded

      • checkOperandTypes

        public boolean checkOperandTypes​(SqlCallBinding callBinding,
                                 boolean throwOnFailure)
        Description copied from interface: SqlOperandTypeChecker
        Checks the types of all operands to an operator call.
        Specified by:
        checkOperandTypes in interface SqlOperandTypeChecker
        Parameters:
        callBinding - description of the call to be checked
        throwOnFailure - whether to throw an exception if check fails (otherwise returns false in that case)
        Returns:
        whether check succeeded

      • getAllowedSignatures

        public java.lang.String getAllowedSignatures​(SqlOperator op,
                                             java.lang.String opName)
        Description copied from interface: SqlOperandTypeChecker
        Returns a string describing the allowed formal signatures of a call, e.g. "SUBSTR(VARCHAR, INTEGER, INTEGER)".
        Specified by:
        getAllowedSignatures in interface SqlOperandTypeChecker
        Parameters:
        op - the operator being checked
        opName - name to use for the operator in case of aliasing
        Returns:
        generated string