Remarks
or Comments
are human-readable comments that help understand the table and column structure. Liquibase
allows adding comments while creating a table, as well as in the Changeset
.
Set Remarks on Single Column
<?xml version="1.1" encoding="UTF-8" standalone="no"?>
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog" xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext" xmlns:pro="http://www.liquibase.org/xml/ns/pro" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd http://www.liquibase.org/xml/ns/pro http://www.liquibase.org/xml/ns/pro/liquibase-pro-latest.xsd http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd">
<changeSet author="wesome" id="1693111591793-1">
<createTable catalogName="appledb" schemaName="appledb" tablespace="appledb" tableName="apple">
<column name="apple_id" type="BIGINT">
<constraints unique="true" primaryKey="true" />
</column>
<column name="apple_name" type="VARCHAR(20)" />
<column name="current_date_time" type="datetime" />
</createTable>
</changeSet>
<changeSet author="wesome" id="1692599548266-1">
<setColumnRemarks catalogName="appledb" columnName="apple_name" remarks="column will store the name of the apples" schemaName="appledb" tableName="apple" columnDataType="VARCHAR(20)" />
</changeSet>
</databaseChangeLog>
liquibase.properties (update changeLog File file format with SQL, XML, YAML, JSON as per changelog.mysql.)
changeLogFile=changelog.mysql.xml
liquibase.command.url:jdbc:mysql://localhost:3306/appleDb?createDatabaseIfNotExist=true&autoReconnect=true&useSSL=false&allowPublicKeyRetrieval=true
liquibase.command.username : root
liquibase.command.password : rootroot
Run command liquibase update
Remarks can be checked on the table by running the command
SHOW FULL COLUMNS FROM appleDb.apple;
Set Remarks on Multiple Column
In order to add remarks on multiple columns
at once, One solution is to have multiple changesets
with each adding remark on a column
, but it will increase redundancy. Liquibase
allows multiple nested setColumnRemarks
tags for each column.
<?xml version="1.1" encoding="UTF-8" standalone="no"?>
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog" xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext" xmlns:pro="http://www.liquibase.org/xml/ns/pro" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd http://www.liquibase.org/xml/ns/pro http://www.liquibase.org/xml/ns/pro/liquibase-pro-latest.xsd http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd">
<changeSet author="wesome" id="1692599548266-1">
<setColumnRemarks catalogName="appledb" columnName="apple_name" remarks="column will store the name of the apples" schemaName="appledb" tableName="apple" columnDataType="VARCHAR(20)" />
<setColumnRemarks catalogName="appledb" columnName="current_date_time" remarks="column will store current date and time" schemaName="appledb" tableName="apple" columnDataType="datetime" />
</changeSet>
</databaseChangeLog>
liquibase.properties (update changeLog File file format with SQL, XML, YAML, JSON as per changelog.mysql.)
changeLogFile=changelog.mysql.xml
liquibase.command.url:jdbc:mysql://localhost:3306/appleDb?createDatabaseIfNotExist=true&autoReconnect=true&useSSL=false&allowPublicKeyRetrieval=true
liquibase.command.username : root
liquibase.command.password : rootroot
Run command liquibase update
Remarks can be checked on the table by running the command
SHOW FULL COLUMNS FROM appleDb.apple;