In Calcite type inference happens during validation, much later than syntax checking. So you cannot decide just based on "syntax" which || is being invoked. Moreover, the presence of type casts may make this tricky. Consider true || 'false'. Depending on the implicit casting rules, this may be interpreted either as a Boolean or as a string. But indeed, if you have your own SqlOperatorTable, and given the existing implicit casts rules, you should be able to implement your desired behavior.
I suspect that Calcite indeed is not prepared to disambiguate overloaded operators based on type - only overloaded functions. But since you have your own SqlOperatorTable, can you make || be a function? I think this only may make a difference if you plan to convert the representation back to SQL using RelToSqlConverter - then having it be a FUNCTION would cause problems. Note: I haven't tried the solution I am proposing - it may not work. Mihai ________________________________ From: Stephen Carlin <scar...@cloudera.com.INVALID> Sent: Sunday, November 3, 2024 2:57 PM To: dev@calcite.apache.org <dev@calcite.apache.org> Subject: Operator overloading for SqlSyntax.BINARY Hi all, I'm currently trying to implement Calcite on my already existing SQL syntax. I created my own SqlOperatorTable and I overrode the lookupOperatorOverloads method. And things are working pretty well. But.... I have a situation with the "||" operator. In my syntax, it can be used as either "concat" or "or". I thought this was gonna be an easy task within the framework. According to my syntax rules (for better or for worse), if both parameters are boolean, it should be an "or". Otherwise, it should be a "concat". My plan was to return both operators in the lookupOperatorOverloads operator list and let the Calcite framework do its thing. That method does not have access to the parametrs. But I did see a filterRoutinesByParameterTypeAndName method which would do exactly what I want! However, the first check in the method is "is it an SqlSyntax.FUNCTION", which...it is not, it's a BINARY. So I'm unable to use this filter and I don't have a way to choose based on parameters. I have to use 2 different operators because the precedence of OR is 22 and CONCAT is 60. I hope this is enough of an explanation of my problem. Any suggestions on how to solve this? I have my own Parser.jj that I'm using so I can theoretically manipulate code there, but I'd like to keep manipulations there to a minimum. Also, is there any reason why the filter routine only wants to filter functions and not binary operators? Thanks in advance, Steve
