Data schema descriptor
Schema description
The schema must be expressed as an XML file. This file should be located at a core addon module and be named plugin-ddl.xml.
This DDL file can contain descriptions for tables, indexes and foreign keys.
Tables
A table is composed of a <table> entity containing one or more <column> entities:
Attributes for <table> entity |
|
name |
Table name |
Attributes for <column> entity |
|
name |
Column name |
type |
It can have one of the following values, as stated at java.sql.Types class: INTEGER LONG BOOLEAN / BIT FLOAT DOUBLE VARCHAR CHAR DATE CLOB BLOB |
length |
Optional column size. |
notNull |
true if it cannot contain null values |
primaryKey |
true if it's part of the primary key. The primary key will be composed of all attributes marked as primary key. The order of them will be the same as their appear order at XML fi |
Foreign keys
A foreign key is declared using the <foreignKey> entity. It will contain one or more <column> entities. Each columns identifies a member of the foreign key. It will also contain one or more <foreignColumn> entities. Each foreignColumn entity specifies the name of the corresponding column at the foreign table.
Attributes for entity <foreignKey> |
|
name |
Foreign key name |
tableName |
Table name |
foreignTableName |
Name of master table |
Attributes for <column> entity |
|
name |
Column containing the foreign key |
Attributes for <foreignColumn> entity |
|
name |
Column containing the foreign key |
Indexes
An index is declared using the <index> entity. It will contain one or more <column> entities. Each column identifies a member of the index.
Attributes for <index> entity |
|
name |
Index name |
tableName |
Table name |
unique | true if no duplicated keys will be allowed |
Attributes for entity <column> |
|
name |
Column to be indexed |
Sample plugin-ddl.xml
<?xml version="1.0" encoding="UTF-8"?>
<database>
<table name="t1">
<column name="id" type="LONG" notNull="true"
autoIncrement="true" primaryKey="true"/>
<column name="vc" type="VARCHAR" length="55"/>
<column name="t1date" type="DATETIME" notNull="true"/>
<column name="userid" type="LONG" />
</table>
<index name="i1" table="t1">
<column name="vc"/>
</index>
<table name="t2">
<column name="id" type="LONG" primaryKey="true"/>
</table>
<foreignKey name="t1_fk" table="t1" foreignTable="t2">
<column name="userid"/>
<foreignColumn name="id"/>
</foreignKey>
</database>