I missed that FAQ entry. Anyway, for future reference, the complete query is: SELECT name FROM sqlite_master WHERE type=”table” AND name=”{table_name}”; Where {table_name} is the name of the table to check. Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database Schema This will return a list of tables with the name … Read more
Note that as of version 3.25.0 released September 2018 you can now use ALTER TABLE to rename a column. Original “create new and drop old table” answer below. Say you have a table and need to rename “colb” to “col_b”: First create the new table with a temporary name, based on the old table definition … Read more
You can’t. SQLite doesn’t support JOINs in UPDATE statements. But, you can probably do this with a subquery instead: UPDATE closure SET checked = 0 WHERE item_id IN (SELECT id FROM item WHERE ancestor_id = 1); Or something like that; it’s not clear exactly what your schema is.
If you never want to have duplicates, you should declare this as a table constraint: CREATE TABLE bookmarks( users_id INTEGER, lessoninfo_id INTEGER, UNIQUE(users_id, lessoninfo_id) ); (A primary key over both columns would have the same effect.) It is then possible to tell the database that you want to silently ignore records that would violate such … Read more
In windows you can try this program http://www.nirsoft.net/utils/opened_files_view.html to find out the process is handling db file. Try closed that program for unlock database In Linux and macOS you can do something similar, for example, if your locked file is development.db: $ fuser development.db This command will show what process is locking the file: > … Read more