creating an interface for sqlite database tutorial

#Creating an interface for sqlite database tutorial code#

Sl3::DbValue::setNull can be used to set a value to Null. If an invalid type is set a sl3::ErrTypeMisMatch will be thrown. sl3::DbValue::set or the assignment operator.If a value is set or read that is omitted by the type property an sl3::ErrTypeMisMatch exception is thrown. If a sl3::DbValue::isNull the storage type is also sl3::Type::Null.īoth properties are used to validate reads and writes at runtime. If the type is Type::Variant values of any type can be used, otherwise it has to be the type specified. This property depends on the actual value sl3::DbValue::getStorageType: The current value type.If the type is sl3::Type::Variant the instance can hold any type, otherwise only the specified type is allowed, one of: This property is assigned at creation and can not be change One defines the type rule, the other the type value. It can be defined if any type is allowed for an instance or only a certain one. This class can be used to read from and write to a sl3::Database.Ī sl3::DbValues can hold different types. If you think on of these features should be supported by the library please file a feature request in the issue tracker. See RowCallback and Callback functions from more infomration. There are 2 ways to do with writing an own sl3::RowCallback or a sl3::Command::Callback. The same is true for the special endianess functions sqlite provides. If UTF-16 string types is wanted this needs to be implement self.

Note Text is a UTF-8 string since this is a good default and keeps things simple. In sqlite a clomun can hold different types and libsl3 supports this concept. Since a database value can also be NULL there is a type for it.

sl3::Type::Blob stands for a sl3::Blob, a char vector.

sl3::Type::Text stands for a std::string.

The types in libsl3 are those which are available in datatypes as sqlite does.

It can be directly used, but it has also a virtual destructor and can be used as a base class. Sl3::Database encapsulates a sqlite database. Requesting data from a database will return a sl3::Dataset with rows of sl3::DbValues where each field is a sl3::DbValue.Īnother and fully customizable way to receive data from a database is covered in the RowCallback and Callback functions section. Sl3::DbValues can also be used to receive data from a database. Parameters are sl3::DbValues, a sl3::Container of sl3::DbValue instances. Slighlty longer build time for building libsl3 (not for programs consuming libsl3)Ī database is represented via sl3::Database.Ī database can execute SQL strings to read or write data.Ī sl3::Command is a compiled SQL statement which can contain parameters.Programs consuming libsl3 do not need to link against sqlite3. This requires doxygen to be found on the system.įor the internal sqlite distribution there are several options to configure sqlite3 available. If set to ON, the doc target will be added. If set to ON, test targets will be added. If set to OFF, the system sqlite3 will be used.

#Creating an interface for sqlite database tutorial code#

If set to ON, the internal sqlite3 source code will be used. On Linux, the configure and build process might appear as follows:ĬMake options to control the build process: If doxygen is not found it will not be possible to build the documentation.ĭoctest is fetched on demand, except if BUILD_TESTING is set to OFF. Optional: doxygen for buliding the documentation.Optional: SQLite3, sqlite is included in the source code.Required: CMake for building the library.The minimum required C++ standard is C++17.The project has the following dependencies: Get you copy of the source code from the libsl3 GitHub repository. Later, when C++11 was new, it became a modern C++11 interface to sqlite. Libsl3 stared as a C++98 project long time ago. The library fully supports the SQLite duck typing concept, but it also offers a means to incorporate type checking when communicating with a database. Reading from and writing to a database is accomplished through SQL and prepared commands, also known as stored procedures. The library does not attempt to function as an ORM (Object-Relational Mapping) and does not introduce C++ syntax resembling SQL for interacting with a SQLite database. Libsl3 enables efficient communication with SQLite3 databases using the natural approach, SQL.