#SQLITE VACUUM UPDATE#
#SQLITE VACUUM MANUAL#
#SQLITE VACUUM FREE#

Nov 28 17:24:38 my.linux.host systemd: Finished Hot-backup Chia blockchain database. Nov 28 17:24:38 my.linux.host systemd: rvice: Succeeded. Nov 28 17:14:30 my.linux.host systemd: Starting Hot-backup Chia blockchain database. Loaded: loaded (/home/chia/.config/systemd/user/rvice static vendor preset: enabled)

#SQLITE VACUUM UPDATE#

the pysqlite driver starts transactions automatically whenever a statement like INSERT, UPDATE or DELETE is detected. theres also nothing about what youre doing above that should have changed with 1.4. rvice - Hot-backup Chia blockchain database i cant reproduce that issue here with SQLite, the 'vacuum' statement doesnt seem to care about being in a transaction or not.To see when the last backup(s) ran and how long it took, you can call: If you ever want to run a backup of the database right now (to, for example, create an up-to-date copy of the database), you can run the following: This output tells you, that the next backup is scheduled for Mon, at 00:06:29 CET. Loaded: loaded (/home/chia/.config/systemd/user/chia-blockchain-backup.timer enabled vendor preset: enabled)Īctive: active (waiting) since Sun 18:56:45 CET 3min 14s ago chia-blockchain-backup.timer - Run Chia blockchain database backup.There are several reasons an application might do this: Unless SQLite is running in 'autovacuumFULL' mode, when a large amount of data is deleted from the database file it leaves behind empty space, or 'free' database pages. $ systemctl -user status chia-blockchain-backup.timer The VACUUM command rebuilds the database file, repacking it into a minimal amount of disk space. To see when the backup will run next, execute:

Systemctl -user enable -now chia-blockchain-backup.timer This timer unit will run a backup once a day, at some random time in the first 15 minutes (900 seconds) past midnight.įinally, enable the automatic backup by running: With systemd user units, first ensure that the path for user units exists:Ĭreate a ~/.config/systemd/user/rvice file, the unit that runs the backup, with the following content:ĭescription=Hot-backup Chia blockchain databaseĮnvironment=DATABASE=%h/.chia/mainnet/db/blockchain_v2_mainnet.sqliteĮxecStart=/usr/bin/sqlite3 $.bak''Ĭreate a ~/.config/systemd/user/chia-blockchain-backup.timer, the unit that schedules automatic runs of the backup, with the following content:ĭescription=Run Chia blockchain database backup (Of course, any other automation method, such as plain cronjobs, will do as well.) Hence, Auto-VACUUM just keeps the database small.If you use a Linux distribution using systemd, you can use systemd's user units to automate the db backup. By doing so it can significantly fragment the database while VACUUM ensures defragmentation.

#SQLITE VACUUM FREE#

SQLite Auto-VACUUM does not do the same as VACUUM rather it only moves free pages to the end of the database thereby reducing the database size. You can also run VACUUM on a particular table as follows − You can run VACUUM from SQLite prompt as well as follows −

#SQLITE VACUUM MANUAL#

Manual VACUUMįollowing is a simple syntax to issue a VACUUM command for the whole database from command prompt − As the VACUUM command rebuilds the database file from scratch, VACUUM can also be used to modify many database-specific configuration parameters.

VACUUM command is a no-op for in-memory databases. VACUUM command will fail if there is an active transaction. It is not possible to VACUUM an attached database file. The VACUUM command only works on the main database. VACUUM command may change the ROWID of entries in tables that do not have an explicit INTEGER PRIMARY KEY. One of the important features of SQLite database is its ability to reclaim unused disk space through a process called VACUUM. This eliminates free pages, aligns table data to be contiguous, and otherwise cleans up the database file structure. VACUUM command cleans the main database by copying its contents to a temporary database file and reloading the original database file from the copy.

Sqlite vacuum