Constant MAX_REGEX_SIZE_BEFORE_COMPILATION

const MAX_REGEX_SIZE_BEFORE_COMPILATION: usize = _; // 1_048_576usize

We also need a separate limit for the size of regexes before compilation. Even though the Regex crate promises that using its size_limit option (which we set to the other limit, MAX_REGEX_SIZE_AFTER_COMPILATION) would prevent excessive resource usage, this doesn’t seem to be the case. Since we compile regexes in envd, we need strict limits to prevent envd OOMs. See https://github.com/MaterializeInc/database-issues/issues/9907 for an example.

Note: This number is mentioned in our user-facing docs at the “String operators” in the function reference.