[CALCITE-6927] Add rule for join condition remove IS NOT DISTINCT FROM #4277
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| //~ Inner Classes ---------------------------------------------------------- | ||
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| /** Shuttle that removes 'x IS NOT DISTINCT FROM y' and converts it | ||
| * to '(COALESCE(x, '') = COALESCE(y, '')) |
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'' is not an accurate description of what's happening.
| RexNode operand1 = tmpCall.operands.get(1); | ||
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| RexNode operand0Zero = | ||
| rexBuilder.makeZeroLiteral(operand0.getType()); |
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this only works if the type is a numeric type.
joins work on arbitrary types, including arrays and maps
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I missed this question. I will think about how to make it compatible with complex types.
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This does not look like a traditional optimization rule, since it does not really change the plan in any way, it just replaces some expressions with equivalent ones. I don't know if there is a better place for it, though. |
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| } | ||
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| for (RexNode op : found.getOperands()) { | ||
| if (op.getType().getSqlTypeName() == SqlTypeName.MAP) { |
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I actually think maps can be compared, but it's fine to skip this case too.
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I referred to the implementation of spark, it does not support map comparison. But I agree with your, map should be comparable. I will skip the map comparison for now, and modify it later if I have more references. WDYT
| if (operand.getType().getSqlTypeName() == SqlTypeName.ARRAY) { | ||
| ArraySqlType arrayType = (ArraySqlType) operand.getType(); | ||
| RelDataType elementType = arrayType.getComponentType(); | ||
| RexNode elementZero = rexBuilder.makeZeroLiteral(elementType); |
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You need to call the function recursively, because ARRAY can have ARRAY as elements.
Also, this may work for MULTISET too.
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there is also the case of ROW types.
Maybe you want to enhance the makeZeroLiteral function to handle these as well?
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Great Idea! I think I can create a new ticket to complete this suggestion first.
please see: CALCITE-6927