Nikolay Shaplov wrote: > I found out, that all relation options of string type in current postgres, > are > actually behaving as "enum" type.
If this patch gets in, I wonder if there are any external modules that use actual strings. An hypothetical example would be something like a SSL cipher list; it needs to be somewhat free-form that an enum would not cut it. If there are such modules, then even if we remove all existing in-core use cases we should keep the support code for strings. Maybe we need some in-core user to verify the string case still works. A new module in src/test/modules perhaps? On the other hand, if we can find no use for these string reloptions, maybe we should just remove the support, since as I recall it's messy enough. > [...] But each time this behavior is implemented as validate function > plus strcmp to compare option value against one of the possible > values. > > I think it is not the best practice. It is better to have enum type > where it is technically enum, and keep sting type for further usage > (for example for some kind of index patterns or something like this). Agreed with the goal, for code simplicity and hopefully reducing code duplication. > Possible flaws: > > 1. I've changed error message from 'Valid values are "XXX", "YYY" and "ZZZ".' > > to 'Valid values are "XXX", "YYY", "ZZZ".' to make a code a bit simpler. If > it > is not acceptable, please let me know, I will add "and" to the string. I don't think we care about this, but is this still the case if you use a stringinfo? > 2. Also about the string with the list of acceptable values: the code that > creates this string is inside parse_one_reloption function now. I think you could save most of that mess by using appendStringInfo and friends. I don't much like the way you've represented the list of possible values for each enum. I think it'd be better to have a struct that represents everything about each value (string name and C symbol. Maybe the numerical value too if that's needed, but is it? I suppose all code should use the C symbol only, so why do we care about the numerical value?). -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
