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12.14. Alter Statement

ALTER statements currently primarily support adding OPTIONS properties to Tables, Views and Procedures. Using a ALTER statement, you can either add, modify or remove a property.
See "alter column options", "alter options", and "alter options list" in Section A.7, “Productions”.

Example 12.8. Example ALTER

ALTER FOREIGN TABLE "customer" OPTIONS (ADD CARDINALITY 10000);
ALTER FOREIGN TABLE "customer" ALTER COLUMN "name" OPTIONS(SET UPDATABLE FALSE)
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ALTER statements are especially useful, when user would like to modify/enhance the metadata that has been imported from a NATIVE datasource. For example, if you have a database called "northwind", and you imported that metadata and would like to add CARDINALITY to its "customer" table, you can use ALTER statement, along with "chainable" metadata repositories feature to add this property to the desired table. The below shows an example -vdb.xml file, that illustrates the usage.

Example 12.9. Example VDB

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<vdb name="northwind" version="1">
    <model name="nw">
        <property name="importer.importKeys" value="true"/>
        <property name="importer.importProcedures" value="true"/>
         <source name="northwind-connector" translator-name="mysql" connection-jndi-name="java:/nw-ds"/>
         <metadata type = "NATIVE,DDL"><![CDATA[
              ALTER FOREIGN TABLE "customer" OPTIONS (ADD CARDINALITY 10000);
              ALTER FOREIGN TABLE "customer" ALTER COLUMN "name" OPTIONS(SET UPDATABLE FALSE);
         ]]>
         </metadata>
    </model>
</vdb>
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