com.bloomberg.selekt.SQLiteAutoVacuumMode.kt Maven / Gradle / Ivy
/*
* Copyright 2020 Bloomberg Finance L.P.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.bloomberg.selekt
enum class SQLiteAutoVacuumMode(private val value: Int) {
/**
* Auto-vacuum is disabled. When auto-vacuum is disabled and data is deleted data from a database, the database file
* remains the same size. Unused database file pages are added to a "freelist" and reused for subsequent inserts. So no
* database file space is lost. However, the database file does not shrink. In this mode vacuum can be used to rebuild
* the entire database file and thus reclaim unused disk space.
*/
NONE(0),
/**
* The freelist pages are moved to the end of the database file and the database file is truncated to remove the
* freelist pages at every transaction commit. Note, however, that auto-vacuum only truncates the freelist pages from
* the file. Auto-vacuum does not defragment the database nor repack individual database pages the way that vacuum does.
* In fact, because it moves pages around within the file, auto-vacuum can actually make fragmentation worse.
*/
FULL(1),
/**
* The additional information needed to do auto-vacuuming is stored in the database file but auto-vacuuming does not
* occur automatically at each commit as it does with "full". In incremental mode, the separate incremental vacuum
* pragma must be invoked to cause the auto-vacuum to occur.
*/
INCREMENTAL(2);
operator fun invoke() = value
}