sqlite-utils add-foreign-keys command

[simonw]

Like add-foreign-key but can do multiple foreign keys at once. Inspired by https://github.com/simonw/calands-datasette/blob/99de39dd80a906f5c1f16724467b0cd55ba4ef36/build.sh which does this:

sqlite-utils add-foreign-key calands.db units_with_maps ACCESS_TYP
sqlite-utils add-foreign-key calands.db units_with_maps AGNCY_NAME
sqlite-utils add-foreign-key calands.db units_with_maps AGNCY_LEV
sqlite-utils add-foreign-key calands.db units_with_maps AGNCY_TYP
sqlite-utils add-foreign-key calands.db units_with_maps LAYER
sqlite-utils add-foreign-key calands.db units_with_maps MNG_AGENCY
sqlite-utils add-foreign-key calands.db units_with_maps MNG_AG_LEV
sqlite-utils add-foreign-key calands.db units_with_maps MNG_AG_TYP
sqlite-utils add-foreign-key calands.db units_with_maps COUNTY
sqlite-utils add-foreign-key calands.db units_with_maps DES_TP

[simonw]

This can accept four arguments: table, column, other_table, other_column:

sqlite-utils add-foreign-keys calands.db \
  units_with_maps ACCESS_TYP ACCESS_TYP id \
  units_with_maps AGNCY_NAME AGNCY_NAME id \
  units_with_maps AGNCY_LEV AGNCY_LEV id

[simonw]

It will call this method:

sqlite-utils/sqlite_utils/db.py

Lines 405 to 411 in 367082e

	def add_foreign_keys(self, foreign_keys):
	# foreign_keys is a list of explicit 4-tuples
	assert all(
	len(fk) == 4 and isinstance(fk, (list, tuple)) for fk in foreign_keys
	), "foreign_keys must be a list of 4-tuples, (table, column, other_table, other_column)"
	foreign_keys_to_create = []