Android Sqlite table column foreign keys? -


i creating simple sqlite db android project. has been long time since have written msql commands, let alone sqlite.

to keep question simple, lets have 2 tables. 1 table dogs , owners.

in dogs there column hold owner's _id primary key other table.

i can't life of me remember how in sqlite or if can.

i creating dog table string :

private static final string create_table_dogs = "create table"             + table_dogs + "(" + column_id             + " integer primary key autoincrement, "             + column_name + " text not null, "             + column_owner + " integer );";

sqlite not have foreign keys enabled default. you'll need execute pragma foreign_keys=on; every time before using database.

to create actual foreign key relation, add column dogs table this: foreign key(owners_id) references owners(_id). should define rules constraint violations.

for more information on sqlite foreign keys, check out https://www.sqlite.org/foreignkeys.html


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