model: Save int-based schema version in DB

Ceres v0.4.0 used the `git describe` output as database schema and
enforced exactly matching versions between the database and the
executable.

This turned out to be not flexible enough. It is way easier to version
the database separately with a simple integer and require the same
database schema version integer between the application and the
database.

This commit implements this new approach.

1 files changed, 8 insertions, 0 deletions

diff --git a/model/sql/migration001.sql b/model/sql/migration001.sql
new file mode 100644
index 0000000..64c7ee3
--- /dev/null
+++ b/model/sql/migration001.sql
@@ -0,0 +1,8 @@
+-- Database schema 1 is the first schema with numerical versioning.
+
+DELETE FROM metadata WHERE key = 'version';
+
+INSERT INTO metadata
+	(key, value)
+VALUES
+	('schema_version', '2');