I'm Trying in the cassandra query language tool DevCenter 1.6.0 to get the date difference from existing table.
There is no such built-in function in CQL - you can potentially implement user-defined function for it, but this will require additional programming in Java, and that will also require changing the cassandra.yaml configuration file to enable support for user-defined functions (see linked documentation for details).
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When building the GRPC libraries from sources, for example on Android, I counter the following issues:
I have to remove libgrpc_unsecure and libgrpc++_unsecure in order
for the initialization of GRPC not to get stuck.
I see that there are two libraries: libprotobuf and libprotobuf-lite.
Which is the differences between them(other than the fact that
probably the lite version contains less functions), which one I
should include?
When generating the .so libraries it is generating also the .a
libraries and if I use the .a libraries a function is not found, so I
have to get back to using the .so, but in that case should I also use
the .a? If not, is there a way to build just the .so?
Is there a link where it specifies the purpose of each library and what should be used? For example I don't think grpc++_reflection is of some use in my case, but how do I know what it contains without having to pass through every symbol in it? I need to better understand how to use the library files.
Yes, libgrpc and libgrpc_unsecure are mutually exclusive. So you need to choose one as a dependency of your application.
Your interpretation is correct. lite version has less feature so you can try lite first and switch to the regular one if it doesn't fit. You may want to check this https://github.com/protocolbuffers/protobuf/blob/main/src/file_lists.cmake to see what's available and what isn't in the lite.
It depends on how you built gRPC.
gRPC has a couple of libraries but grpc++ is the one you want to link against. I don't think it has a comprehensive doc for what is for what so checking out https://github.com/grpc/grpc/blob/master/CMakeLists.txt is the best thing you can do to understand what features those libraries provide.
Coming from an R background, and just started learning Julia, I wonder how's documentation in Julia, and if there are analogues to R's help pages and vignettes.
Furthermore, in R, one can document functions using roxygen comment blocks, is there also something similar in Julia?
I think it is best to understand how things work by example. I will comment on how DataFrames.jl is documented as this is a pretty standard approach:
Functions are documented using docstrings, here is an example of a docstring of function names; These docstrings are then discoverable interactively via help system (by pressing ?)
A standard way to generate a documentation for a package is to use Documenter.jl; by the way: the package has a great team of maintainers who are very helpful and responsive; here you have a link to the make.jl file that is executed to generate the documentation; note in particular the option doctest=true which makes sure that all code examples that are properly anoteted following Documenter.jl rules are producing an expected output
In order to set-up auto-generation of package documentation you need to set up CI integration on GitHub; again - there are many ways to do it; a standard one is to use GitHub Actions; here you have a link to the part of the ci.yml specification file that ensures that documentation is built as a part of CI; then in any PR, e.g. this one (I am giving a link to a currently open PR that is documentation related) you can see in the section reporting CI results that after running tests also documentation was generated. Here you can see how a documentation generated using this toolchain looks like (e.g. note that at the bottom you can switch the version of the package you want to read manual of dynamically which shows you that all here is really well integrated - not just a bunch of PDF or HTML files).
I hope this will help you to get started. I have pointed you to all essential pieces that are normally used by packages hosted on GitHub (i.e. this is not the only way to do it, but it is a standard way most commonly used).
To master all the details of the above you need to read the documentation in the Julia Manual and Documenter.jl carefully. Unfortunately writing a proper documentation is not easy (in any programming language). The good thing is that Julia has a really excellent toolchain that supports this process very well.
What's the difference between sqlite and better-sqlite3 implementations? I have to use better-sqlite3 to create a database for a form (+ only node.js and express), but the only clear example I found uses sqlite. Is there any difference? If not, thanks. Otherwise, do you know any usefull links for databases and forms with better-sqlite3?
Thanks
In better-sqlite3, you can register custom functions and aggregate functions written in JavaScript, which you can run from within SQL queries.
In better-sqlite3, you can iterate through the cursor of a result set, and then stop whenever you want (you don't have to load the entire result set into memory).
In better-sqlite3, you can conveniently receive query results in many different formats (here, here, and here).
In better-sqlite3, you can safely work with SQLite's 64-bit integers, without losing precision due to JavaScript's number format.
See https://github.com/JoshuaWise/better-sqlite3/issues/262
One important difference is: better-sqlite allows for synchronous SQLite queries. With sqlite, you can't do that.
In order to create a simple annotation that logs function calls, I'm trying to grab the following attributes from a function that has said annotation:
Function name
Parameter names
Parameter values
What I have so far uses KCallable as a value, which makes grabbing the name and names from the list of KParameter fairly simple. However, I cannot figure out how to get the values of said parameters to make the log statement more contextual.
Does anyone have ideas on grabbing these parameters values within the annotation? It doesn't need to use KCallable, that just seemed like the most intuitive receiver.
You will need a different approach. Annotations and parameter type are a compile time features while values are a runtime feature.
What you will have to do is use a bytecode processing framework like ASM or google "aspect oriented programming". That allows you to examine the generated bytecode and modify if before the JVM tries to execute it.
The other approach is to write a Kotlin compiler plugin which generates the necessary code (google "Writing Your First Kotlin Compiler Plugin")
This blog post contains an example for Java and Spring using the AOP approach: https://solocoding.dev/blog/eng_spring_centrlize_logging_with_aop
I recommend the compiler plugin because the other approach is much more complicated, brittle and badly documented. Use AOP only if you find a framework which already contains all the features you need.
Which tools exist for static analysis of XQuery functions?
Example tasks: given two XSD schemas A and B and some XQuery f, check that for any document d of type A its transformation f(d) is valid against B.
Or for given query generate its inverse, when exists.
This topic is unfortunately hard for googling.
Yes, I think OxygenXML is fantastic for XQuery analysis, it has its own manual static-analysis tools built in.
You can use the manual validation instead: Document > Validate > Validate after configuring a transformation or a validation scenario that specified the xDB connection as the engine.
Other resources I found which where interesting on this topic Using XML Editor to Create or Validate an OLAC Static Repository and Where can I find static/dynamic code analysis tools for XSLT? (Oxygen can be used with X-Query, X-Path, XLink to name a few).