
Fix the database migration that adds `NOT NULL` clauses. It used `INSERT INTO temp_x SELECT * from x;`, and the `*` returns the fields in the order they are defined on the table. Since this might be different from the order that the `INSERT INTO temp_x` expects, strange problems can happen where columns get swapped (or constraints can fail on columns that they should not fail for, because they got fed data from a different column).
SQL Migrations
The files here are run by Goose, the database migration tool.
These are embedded into the Flamenco Manager executable, and automatically run on startup.
Foreign Key Constraints
Foreign Key constraints (FKCs) are optional in SQLite, and always enabled by
Flamenco Manager. These are temporarily disabled during database migration
itself. This means you can replace a table like this, without ON DELETE
effects running.
INSERT INTO `temp_table` SELECT field1, field2, etc FROM `actual_table`;
DROP TABLE `actual_table`;
ALTER TABLE `temp_table` RENAME TO `actual_table`;
Note that the SELECT
clause lists each field specifically. This is to ensure
that they are selected in the expected order. Without this, data can get
mangled.