Monadic interface to sqlite
The Lemonade Sqlite project aims at providing high-level, easy to use, monadic bindings for sqlite3 in OCaml.
Provide detailed error descriptions and easy error management by performing database operations in a success monad.
Query rows as a monadic stream. A monadic stream is similar to a normal stream but reading from the stream is performed in the success monad, thus conveying neatly error conditions to the application level.
Insert rows read from a monadic stream. This allows to easily map complex data structures to the database rows scattered through several tables, because it easy to combine streams together.
Optionally initialise the database with a SQL script when creating it.
These techniques are illustrated by the example
example/BatchCollection.ml implementing operations to read and write
items of batch job journal to a database. In this example, a
journal of batch jobs, describing requests (table batch_index) the
details of the corresponding query jobs (table batch_query) and the
details of the computed answer (table batch_answer) is randomly
generated, written to the database and retrieved.
It is easy to install Lemonade Sqlite using opam and its pinning feature. In a shell visiting the repository, say
% autoconf % opam pin add lemonade-sqlite .
It is also possible to install Lemonade Sqlite manually. The installation procedure is based on the portable build system BSD Owl Scripts written for BSD Make.
Verify that prerequisites are installed:
Get the source, either by cloning the repository or by exploding a distribution tarball.
autoconfto produce a configuration script. This is only required if the script is not already present.
./configure, you can choose the installation prefix with
make testto test your build.
Depending on how BSD Make is called on your system, you may need to
bmake in steps 5, 6, and 7.
The GNU Make program usually give up the ghost, croaking
*** missing separator. Stop. when you mistakingly use it instead of
Step 7 requires that you can
su - if you are not already
Michael Grünewald in Bonn, on Mar 16, 2016