Affects Version/s: None
Fix Version/s: 1.1.0-incubating
select ANY type || ANY type ... leads assertion error from:
assert (precision >= 0) || (precision == RelDataType.PRECISION_NOT_SPECIFIED);
(SqlTypeFactoryImpl.java( line: 62))
Essentially, it is because, SqlReturnTypeInference of `||` is DYADIC_STRING_SUM_PRECISION. When doing inference for the return type, there is one data field in DYADIC_STRING_SUM_PRECISION called "precision", which is calculated as arg0.precison + arg1.precision.
However, for ANY type, the precision is defined as -1. So the above calculation will give "-2" for ANY type operands, in turn, breaking up the assertion.
Moreover, `||` can fail when the two operands have different types (e.g., ANY type || String). In the No schema system, ANY type can be quite prevalent. For example, select ANY type || string || ANY type ... where, in addition to two ANY types on two sides, we have a string in between.