Sqlite database backup: the .dump command

Let’s go on mastering our sqlite3 knowledge.
SQLite database is really just a file: a backup it’s as simple as copying one file.

The .dump command shows information about all the changes performed onto the database. Less pieces of information to the hidden file can be found in your home/user typing: $ ~/.sqlite_history.

$ sqlite3 test.db “.dump”

The result is:
PRAGMA foreign_keys=OFF;
BEGIN TRANSACTION;
CREATE TABLE n(id INTEGER PRIMARY KEY, f TEXT, l TEXT);
INSERT INTO “n” VALUES(1,’linus’,’torvalds’);
INSERT INTO “n” VALUES(2,’richard’,’stallman’);
COMMIT;

If you want to backup the database in a new file, you can specify a name (ex. “dbbackup”):
$ $ sqlite3 test.db ‘.dump’ > dbbackup

The contents of the backup can be modified.
For example you can filter and pipe it to another database. Below, table “n” is changed to “people” with the sed command, and it is piped into the “computer_pioneers” database.

$ sqlite3 test.db “.dump”|sed -e s/n/people/|sqlite3 computer_pioneers.db
The contect is the same:
$sqlite3 computer_pioneers.db “select * from people”;