Or changing the datatype for a column, for example. Or PRIMARY KEY, adding CHECK or FOREIGN KEY or NOT NULL constraints,
#Sqlitestudio foreign key to same table full
The full procedure above is appropriate for dropping a column,Ĭhanging the order of columns, adding or removing a UNIQUE constraint Schema change causes the information stored in the table to change. The procedure above is completely general and will work even if the
If foreign key constraints were originally enabled then run PRAGMAįoreign_key_check to verify that the schema change did not break.Them with whatever changes are necessary to accommodate the schema Schema change, then drop those views using DROP VIEW and recreate
If any views refer to table X in a way that is affected by the.Triggers and indexes saved from step 3 above as a guide, makingĬhanges as appropriate for the alteration. Use CREATE INDEX and CREATE TRIGGER to reconstruct indexes and.Change the name of new_X to X using: ALTER TABLE new_X RENAME TO X.Transfer content from X into new_X using a statement like: INSERT.Make sure that the name "new_X"ĭoes not collide with any existing table name, of course. Use CREATE TABLE to construct a new table "new_X" that is in theĭesired revised format of table X.One way toĭo this is to run a query like the following: SELECT type, sql FROM This information will be needed in step 8 below. Remember the format of all indexes and triggers associated with.If foreign key constraints are enabled, disable them using PRAGMA.The steps to make arbitraryĬhanges to the schema design of some table X are as follows: However,Īpplications can make other arbitrary changes to the format of a table "rename table" and "add column" commands shown above. The only schema altering commands directly supported by SQLite are the
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