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Sqlite regex less than 10
Sqlite regex less than 10










sqlite regex less than 10
  1. Sqlite regex less than 10 drivers#
  2. Sqlite regex less than 10 portable#
  3. Sqlite regex less than 10 code#

For example, you can do this as follows, to locate MySQL: this is required for PostgreSQL and SQLite).

sqlite regex less than 10

You should prefer this method if module needs to set properties for the provided target libraries (e.g. In some cases it's more convenient to use CMAKE_INCLUDE_PATH and CMAKE_LIBRARY_PATH variables to locate required libraries. This is especially useful if the package provides its own set of system libraries that should not be recognized by the build routine.

Sqlite regex less than 10 drivers#

When you configure drivers in the manner described above, CMake skips any dependency checks and uses the provided paths as is.

Sqlite regex less than 10 code#

Cross-provider code is always a lot of work and care.īottom line: I think adding those as some kind of provider-specific bool Match(string, string) with no attempt to look at the regex itself is useful, simple and the way to go.C:\ Qt\ 6.0.0\Src\configure. In fact, even basic operations can't be bridged between providers, did you know that 'abc' + null does not yield the same result in SQL Server and Oracle? Try to blindly port your code from one to the other now 🤣. I see linq2db more as "full access to RDMBS power" than a "minimal common layer between all RDBMS". In fact I have mapped Oracle regexp_like myself because we need to use it in our queries. (2) On the other hand, just like all other provider-specific SQL extensions linq2db exposes, I see value in using these functions even when they're not portable. I can foresee the bug reports on specific RDBMS or even RDBMS point releases, the issues asking support for a provider-specific non-standard extension that is not in your lingua franca, etc. It opens a long-term, huge, can of worms.Users will be confused as they need to learn a different regex flavor than the actual one from their db (speaking from experience, I have to use 3 different regexes flavors at my job and man it's mentally taxing).It won't work for dynamically built regexes based on data.It will incur extra parsing/compilation work at runtime.It's a very big task that requires a lot of difficult effort and testing.(1) I don't see why someone would attempt to create an abstraction layer to unify all regexps flavors: Users will have hard time understanding why are there error messages returned by SQL Server when their perfect LINQ to DB should just run. I think implementing a simple generic wrappers is doable, but it's going to be a supportability nightmare.

Sqlite regex less than 10 portable#

So, having a truly portable regular expressions in LINQ to DB is a hard task. If you want more information, please check your favorite engine's documentation. Then the flavor of supported regexps will be whatever the extension provide.

  • In SQLite there's the REGEXP keyword, but it doesn't have the regular expression functionality until you load an extension containing the regexp() function.
  • In R and Python you have to CREATE EXTERNAL LANGUAGE and then use sp_execute_external_script with a bunch of code, and for Java you have to compile it upfront and load into the server with CREATE EXTERNAL LIBRARY.
  • NET you have to have a database into which you'll import the CLR functions with CREATE ASSEMBLY followed by several CREATE FUNCTIONs and during runtime qualify the functions with the DB name. And to use it you first have to set it up: You then have 4 flavors of regular expressions possible - each of those differs a bit from the others. If you want it, you have to resort to using a CLR integration (for example this library), or one of the external languages available in latest versions: R, Java or Python.
  • SQL Server doesn't have any RE support by default.
  • sqlite regex less than 10

    Oracle generally implements POSIX Regular Expressions but also includes selected parts of PCRE.PostgreSQL uses POSIX Regular Expressions with some extensions borrowed from Perl and Tcl, calls them "ARE".Starting with MySQL 8.0.4, ICU’s Regular Expressions package is used.Prior to 8.0.4, MySQL was using the Henry Spencer regular expression library to support regular expression operations.It's pretty much standardized, but only to a limited degree. Only some basic regular expressions, using the common subset of features may work. Of course regular expression syntax can have subtle differences in every engine, even in different versions of the same engine.












    Sqlite regex less than 10