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How to define a default set of columns in Liquibase, def. PKs, def. indices, def. values ​​to create the table?

I'm just looking around to reduce the effort and error when creating a table on lipibase.

Can I create a set of standard columns for tables?

columns:

  • int ID
  • varchar UUID
  • timestamp createdTs
  • timestamp updatedTs
  • int lockVersion

restrictions

  • Identifier is not NULL and with autogenerated key (as primary key)
  • UUID is not NULL
  • createdTS is not NULL with default CURRENT_TIMESTAMP
  • updatedTS is not NULL with default CURRENT_TIMESTAMP
  • lockVersion is not NULL

Index

  • ID
  • UUID

so for example: genericTable.xml

<changeSet author="me" id="myCsId">
   <column name="id" type="int" />
   <column name="uuid" type="varchar(255)" />
   <column name="rowCreated" type="datetime" />
   <column name="rowUpdated" type="datetime" />
   <addNotNullConstraint columnName="id" schemaName="${schema}" tableName="???" columnDataType="int" />
   <addNotNullConstraint columnName="uuid" schemaName="${schema}" tableName="???" columnDataType="varchar(255)" />
   <addNotNullConstraint columnName="rowCreated" schemaName="${schema}" tableName="???" columnDataType="timestamp" />
   <addNotNullConstraint columnName="rowUpdated" schemaName="${schema}" tableName="???" columnDataType="timestamp" />
   <addPrimaryKey columnNames="ID" constraintName="pk_myKey" schemaName="${schema}" tableName="???" />
   ....
</changelog>

and now create another change log like:

<changeSet author="me" id="myCrazyLazyTable1">
   <include file="genericTable.xml" /> <!-- how to pass values like myCrazyLazyTable1 to only this included region to replace the above ??? -->
   <column name="anyadditionlColumn" type="int"/>
</changeset>

<changeSet author="me" id="myCrazyLazyTable2">
   <include file="genericTable.xml" /> <!-- how to pass values like myCrazyLazyTable2 to only this included region to replace the above ??? -->
   <column name="anyadditionlColumn" type="int"/>
</changeset>

can someone help me in the dark?

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2 answers


I have some hints, but I cannot solve the problem with hints. So I had to play around to find a solution. Since I like the complete examples here is an example of work. This example shows how to create a reusable default table structure for default columns and default values.

my MasterChangelog.xml referencing changes / changelists

<?xml version="1.0" encoding="UTF-8"?>
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.3.xsd
        http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd">

   <!-- You can replace the XML-files between the brackets with your XML-files. -->
   <!-- Caution! You have to save your XML-files in the same Folder that contains the MasterChangelog.xml -->

   <include relativeToChangelogFile="true"  file="001_CreateTranslations.xml" />

</databaseChangeLog>

now the changelog itself is 001_CreateTranslations.xml. It reuses the 000_DefaultTable.xml table template as well as some reusable properties in 000_DefaultProperties.dtd. So this example creates in the first changeset a default table structure with the desired table name and in the second changeset creates an additional column with the xml tag of the addColumn tag

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE defaultProperties SYSTEM "000_DefaultProperties.dtd">
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.3.xsd
    http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd">

    <!-- include the default properties -->
    &propertiesAll;

    <property name="table.schema" value="${schema}" />
    <property name="table.name" value="Translations" />
    <property name="table.author" value="cilap" />
    <property name="changeset.number" value="001" />
    <property name="changeset.operation" value="Create" />
    <property name="changeset.name" value="${changeset.number}_${changeset.operation}${table.name}" />

    <!-- create default table ${table.name} -->
    <include file="000_DefaultTable.xml" relativeToChangelogFile="true" />

    <changeSet author="${table.author}" id="${changeset.name}">
        <addColumn schemaName="${schema}" tableName="${table.name}">
            <column name="country" type="VARCHAR(255)" />
        </addColumn>
    </changeSet>
</databaseChangeLog>


my XML objects are in 000_DefaultProperties.dtd

<!ENTITY propertyNow "
   <property name='now' value='sysdate' dbms='oracle' />
   <property name='now' value='now()' dbms='mysql' />
   <property name='now' value='CURRENT_TIMESTAMP' dbms='h2' />
   <property name='now' value='CURRENT_TIMESTAMP' dbms='postgresql' />
" >
<!ENTITY propertySchema "
   <property name='schema' value='redd' dbms='mysql' />
   <property name='schema' value='PUBLIC' dbms='h2' />
" >
<!ENTITY propertiesAll "&propertySchema; &propertySchema;" >

and my default table / template is 000_DefaultTable.xml

<?xml version="1.0" encoding="UTF-8"?>
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog 
    http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.3.xsd
    http://www.liquibase.org/xml/ns/dbchangelog-ext 
    http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd">

    <!-- default changeset for a standard table to use -->
    <!-- set the properties -->
    <!-- <property name="table.schema" value="${schema}" /> -->
    <!-- <property name="table.name" value="Translations" /> -->
    <!-- <property name="table.author" value="cilap" /> -->
    <!-- <property name="changeset.number" value="001" /> -->
    <!-- <property name="changeset.operation" value="Create" /> -->
    <!-- <property name="changeset.name" value="${changeset.number}_${changeset.operation}${table.name}" /> -->

    <changeSet author="${table.author}" id="${changeset.name}Default">
        <createTable schemaName="${table.schema}" tableName="${table.name}">
            <column name="Id" type="int" />
            <column name="Uuid" type="varchar(255)" />
            <column name="RowCreated" type="datetime" />
            <column name="RowUpdated" type="datetime" />
        </createTable>

        <!-- mandatory not null constraints on default columns -->
        <addNotNullConstraint columnName="Id" schemaName="${table.schema}" tableName="${table.name}" columnDataType="int" />
        <addNotNullConstraint columnName="Uuid" schemaName="${table.schema}" tableName="${table.name}" columnDataType="varchar(255)" />
        <addNotNullConstraint columnName="RowCreated" schemaName="${table.schema}" tableName="${table.name}"
        columnDataType="datetime" />
        <addNotNullConstraint columnName="RowUpdated" schemaName="${table.schema}" tableName="${table.name}"
        columnDataType="datetime" />

        <!-- create primary key -->
        <addPrimaryKey columnNames="Id" constraintName="pk_${table.name}" schemaName="${table.schema}" tableName="${table.name}" />
        <addAutoIncrement tableName="${table.name}" columnName="Id" columnDataType="int" />

        <!-- create unique index on uuid -->
        <createIndex indexName="Idx${table.name}Uuid" schemaName="${table.schema}" tableName="${table.name}" unique="true">
            <column name="Uuid" type="varchar(255)" />
        </createIndex>
    </changeSet>
</databaseChangeLog>
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There is nothing in Liquibase to support this.

The easiest way is to use XML Document Objects, which are purely XML Layers and therefore transparent to Liquibase. They will allow you to include a common XML file in your change files.



A more sophisticated approach is to use the Liquibase Extension System ( http://liquibase.org/extensions ), which allows you to override the logic to convert changeSets to SQL. This will allow you to inject any logic you require, including generic data types, standard columns, or whatever.

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