Class IntervalOperandTypeChecker

All Implemented Interfaces:
SqlOperandTypeChecker, SqlSingleOperandTypeChecker

public class IntervalOperandTypeChecker extends Object implements SqlSingleOperandTypeChecker
Parameter type-checking strategy whether the operand must be an interval.
  • Method Details

    • checkSingleOperandType

      public boolean checkSingleOperandType(SqlCallBinding callBinding, SqlNode operand, 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.

      Caution that we could not(shouldn't) implement implicit type coercion for this checker, implicit type coercion has side effect(modify the AST), if this single operand checker is subsumed in a composite rule(OR or AND), we can not make any side effect if we can not make sure that all the single operands type check are passed(with type coercion). But there is an exception: only if the call has just one operand, for this case, use SqlOperandTypeChecker.checkOperandTypes(org.apache.calcite.sql.SqlCallBinding, boolean) instead.

      Specified by:
      checkSingleOperandType in interface SqlSingleOperandTypeChecker
      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
      operand - 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)
      whether check succeeded
    • getAllowedSignatures

      public String getAllowedSignatures(SqlOperator op, 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
      op - the operator being checked
      opName - name to use for the operator in case of aliasing
      generated string