DATABASECHANGELOG table
Liquibase uses the DATABASECHANGELOG table to track which changesets have been run. If the table does not exist in the database, Liquibase creates one automatically.
Columns
The table tracks each changeset as a row, identified by a combination of the id, author, and filename columns. There is no primary key on the table. This is to avoid any database-specific restrictions on key lengths. The composite of id, author, and filename
is unique across all rows of the table.
| Column | Standard data type | Description |
|---|---|---|
ID
|
VARCHAR(255) | Value from the changeset id attribute. |
AUTHOR
|
VARCHAR(255) | Value from the changeset author attribute. |
FILENAME
|
VARCHAR(255) | Path to the changelog. This may be an absolute path or a relative path depending on how the changelog was passed to Liquibase. For best results, it should be a relative path. The logicalFilePath attribute can be used on the changelog or on individual changesets. |
DATEEXECUTED
|
DATETIME | Date/time of when the changeset was executed. Used with ORDEREXECUTED to determine rollback order. |
ORDEREXECUTED
|
INT | Order that the changesets were executed. Used in addition to DATEEXECUTED to ensure order is correct even when the databases datetime supports poor resolution.NOTE: The values are only guaranteed to be increasing within an individual update run. There are times where they will restart at zero. |
EXECTYPE
|
VARCHAR(10) | Description of how the changeset was executed. Possible values include EXECUTED, FAILED, SKIPPED, RERAN, and MARK_RAN. |
MD5SUM
|
VARCHAR(35) | Checksum of the changeset when it was executed. Used on each run to ensure there have been no unexpected changes to changesets in the changelog file. |
DESCRIPTION
|
VARCHAR(255) | Short auto-generated human readable description of changeset |
COMMENTS
|
VARCHAR(255) | Value from the changeset comment attribute. |
TAG
|
VARCHAR(255) | Tracks which changeset correspond to tag operations. |
LIQUIBASE
|
VARCHAR(20) | Version of Liquibase used to execute the changeset. |
CONTEXTS
|
VARCHAR(255) | Context(s) used to execute the changeset. |
LABELS
|
VARCHAR(255) | Label(s) used to execute the changeset. |
DEPLOYMENT_ID
|
VARCHAR(10) | changesets deployed together will have the same unique identifier. |