This adds a compile time concept to determine if from_chars has
floating-point support and uses fallbacks if not.
This is a C++17 feature but support for floats was only added to
libstdc++ with GCC 11.1 and LLVM libc++ in 20.0 (unreleased).
This adds support for using prepared statements for MySQL queries. It is
intended for use in a database quest API but it can be used in source
with some caveats:
- It uses exceptions for error handling instead of returning a fake
result that needs checked. Usage must be wrapped in try/catch.
- DBcore has a connection mutex which indicates the connection might be
shared with other threads. This mutex is locked for certain stmt
operations in an attempt to make it safe to use with multi threaded
connections.
- Prepared statements should only be used on the main thread since the
internal logging is not synchronized.
- Unlike the current query API which retrieves all results as strings,
results are stored in buffers that represent the db field type.
Getter functions are available to retrieve values as desired types.
