![]() Vacuum will take care of such fragmented data. As an additional benefit, it will also put together the data which is fragmented in the database file – if you inserted or updated the data in various tables, the data is saved in different places. database name is always unique and it is case-sensitive. You just have to delete the file manually. This command will rebuild the database file and repack it to occupy the minimal amount of disk space. SQLite Drop Database Like most relational database systems, SQLite does not use the DROP DATABASE command to drop a database and there is no special syntax or steps to drop the database in SQLite. If you want the SQLite to free up the drive space by shrinking the database file, here is the command for you: VACUUM This is because the data is not removed from the disk itself, they are simply marked as removed and the engine is not taking care of them anymore. My database file is big…Įven if you remove all of your data from the SQLite database, the database file will not change the size. Simple, isn’t it? In the SQLite it will work fast enough and it will do what it should. SQLite allows you to drop only one table at a time. The statement is simple as follows: DROP TABLE IF EXISTS schemaname.tablename In this syntax, you specify the name of the table which you want to remove after the DROP TABLE keywords. This means that if you want to remove all data from the table use: DELETE FROM To remove a table in a database, you use SQLite DROP TABLE statement. The deleted data is not saved to the logs. ![]() But on the other hand, there is also no operation log as in “big SQL engines”. This is why I’m using truncate to deal with not important data So, how to truncate in SQLite? So, if the delete is safer, why would I use truncate? Mostly for the sake of performance – the delete operation takes longer, especially if there is serious amount of data to remove. On the other hand, truncate removes the data and in the logs, there is only the information that such an operation took place. In case of any issue, the operation can be reverted by the engine. What is the difference between truncate and delete? In the databases such as MySQL, Postgres or Oracle, the delete operation saves all of the removed data to the logs. Surprisingly there is no truncate statement in the SQLite. In most cases, however, I only want to get rid of data but leave the empty table in place. Of course, if the table is no longer needed, I can delete the whole table. In the typical engine such as MySQL or Postgres, once the data is not needed anymore I use truncate to remove the data from the table. In some of my projects, the database tables are getting bigger and bigger. What is most important for me – it is easy to use and it only takes a file copy to perform the database backup. You can also (or alternatively) prefix the table name with temp, which indicates that it will be created in the temporary database. The difference is that you use either the TEMP or TEMPORARY keyword. ![]() To create a temporary table, you use the same syntax as creating a regular table. The database engine is fast, small and serves well for small amounts of data. A temporary table is created in the temp database. For my pet projects, I’m using SQLite a lot.
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