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Diffstat (limited to 'rust/migrations/00000000000000_diesel_initial_setup/up.sql')
-rw-r--r-- | rust/migrations/00000000000000_diesel_initial_setup/up.sql | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/rust/migrations/00000000000000_diesel_initial_setup/up.sql b/rust/migrations/00000000000000_diesel_initial_setup/up.sql new file mode 100644 index 00000000..3400c7c5 --- /dev/null +++ b/rust/migrations/00000000000000_diesel_initial_setup/up.sql @@ -0,0 +1,37 @@ +-- This file was automatically created by Diesel to setup helper functions +-- and other internal bookkeeping. This file is safe to edit, any future +-- changes will be added to existing projects as new migrations. + + + + +-- Sets up a trigger for the given table to automatically set a column called +-- `updated_at` whenever the row is modified (unless `updated_at` was included +-- in the modified columns) +-- +-- # Example +-- +-- ```sql +-- CREATE TABLE users (id SERIAL PRIMARY KEY, updated_at TIMESTAMP NOT NULL DEFAULT NOW()); +-- +-- SELECT diesel_manage_updated_at('users'); +-- ``` +CREATE OR REPLACE FUNCTION diesel_manage_updated_at(_tbl regclass) RETURNS VOID AS $$ +BEGIN + EXECUTE format('CREATE TRIGGER set_updated_at BEFORE UPDATE ON %s + FOR EACH ROW EXECUTE PROCEDURE diesel_set_updated_at()', _tbl); +END; +$$ LANGUAGE plpgsql; + +CREATE OR REPLACE FUNCTION diesel_set_updated_at() RETURNS trigger AS $$ +BEGIN + IF ( + NEW IS DISTINCT FROM OLD AND + NEW.updated_at IS NOT DISTINCT FROM OLD.updated_at + ) THEN + NEW.updated_at := current_timestamp; + END IF; + RETURN NEW; +END; +$$ LANGUAGE plpgsql; + |