Attempting to insert a row into the track table that does not correspond to any row in the artist table will fail, as will attempting to delete a row from the artist table when there exist dependent rows in the track table There is one exception: if the foreign key column in the track table is NULL, then no corresponding entry in the artist table. But it won't let me commit the new constraint, I believe because it is trying to apply it to the entire column. This way, the constraint is enforced by SQLite.
I deleted the data row with the conflicting data (From: 2.2, To: 2.9) and committed the change before trying to add the new constraint check. db.execSQL ('alter table child add column newCol integer REFERENCES parent (parentId)') Then copy the parentId data to the newCol and then delete the ParentId column. Pb NUMERIC CONSTRAINT CHECK ( (Pb < 50) ), The correct way to add the foreign key constraint to an existing table is the following command. Zn NUMERIC CONSTRAINT CHECK ( (Zn < 50) ), Here is the table definition that I am trying: CREATE TABLE assay (ĬONSTRAINT REFERENCES collar (BHID) ON DELETE CASCADEĬONSTRAINT CHECK ( ("TO" > "FROM") ),Īg NUMERIC CONSTRAINT CHECK ( (Ag "FROM") )ĬONSTRAINT CHECK ( ('From' NOT BETWEEN 'From' AND 'To') ),Īg NUMERIC CONSTRAINT CHECK ( (Ag < 1000) ), I don't understand whether the check is trying to be applied on a row by row basis, which I want, or on a primary key basis. So far I've tried adding a constraint check of ('From' NOT BETWEEN 'From' and 'To) but to no avail. The schema table looks like this: CREATE TABLE sqliteschema ( type text, name text, tblname text, rootpage integer, sql text ) The sqliteschema table contains one row for each table, index, view, and.
I don't want this for a query, but rather as a data-entry check built into the table. The schema for a database is a description of all of the other tables, indexes, triggers, and views that are contained within the database. With the example above I have checks in place that will catch any duplicate 'From' in each hole, but sample #3 is not a duplicate so it will not be caught, but it is an overlapping interval. I need to place a check in my SQLite3 database that ensures that the user cannot enter data with overlapping intervals.
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