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Every UM plugin has its own database schema level counter that implicitly starts at level “0”. (The value of this counter is internally kept in the database and managed by the CSE class PluginSchemaMigration
).
To implement a schema level update, two steps must be taken:
The new numeric schema level must be specified in the plugin’s descriptor file.
The actual schema update must be implemented.
Define new schema level in plugin descriptor
If your plugin descriptor file does not already contain it, add a new property named dbSchema
and give it the value 1
. If your plugin descriptor file already contains the dbSchema
property, just increase its value by one.
Your plugin.desc.json
should look like this:
Codeblock | ||
---|---|---|
| ||
{
"$schema": "http://git.intra.pinuts.de/cmsbs/cmsbs/raw/master/doc/json-schemas/plugin.desc.json",
"__encoding": "Pinuts File Encoding: UTF-8",
"name": "de.acme.tutorial",
...,
"dbSchema": 1
} |
Implement schema update
Create a new ES6 file in your plugin’s CSE directory. If your plugin’s name is de.acme.tutorial
then cmsbs-conf/cse/plugins/de.acme.tutorial/callback/DbSchemaUpdate.mjs
would be a good choice:
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| ||
/// <reference path="../../../.vscode.js"/> const SQL = UM.config.sql; export default class DbSchemaMigration extends PluginSchemaMigration { schemaUpdate_0_1(scr) { // Create column for primary attribute "new_attribute": this.primaryAddColumn(scr, UM.config.getAttribute('new_attribute')); // Alter primary attribute's column according to the current settings from *.attributes file: this.primaryModifyColumn(scr, UM.config.getAttribute('altered_attribute')); // Create column for new table attribute's column: this.tableAddColumn(scr, UM.config.getAttribute('table_attribute->new_column')); // Alter table attribute's column according to the current settings from *.attributes file: this.tableModifyColumn(scr, UM.config.getAttribute('table_attribute->altered_column')); // Issue SQL statement to create an INDEX: this.primaryAddIndex(scr, UM.config.getAttribute('new_attribute')); // Issue SQL statement to mass-update some user entries: const update1 = new SqlQuery(`UPDATE ${SQL.qualifyTable('users')} SET p_entrytype='user' WHERE p_entrytype IS NULL`); scr.add(update1); // Issue SQL statement to mass-update some user entries: const update2 = new SqlQuery(`UPDATE ${SQL.qualifyTable('users')} SET p_entrytype='customer' WHERE p_entrytype='user'`); scr.add(update2); } } // Don't forget to export the class to the respective namespace: de.acme.tutorial.DbSchemaMigration = DbSchemaMigration; |
The method schemaUpdate_0_1
will be executed upon UM startup whenever the recorded schema level for the plugin de.acme.projectx
is below “1”.
To implement a second schema update, just increase the dbSchema
counter in your plugin descriptor file and implement the schemaUpdate_1_2
method.
There are several helper methods available to accomplish common tasks like adding or altering columns or executing custom SQL statements:
Hinweis |
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Please keep in mind that a database schema update cannot be undone automatically! Have a fresh backup at hand to be able to rollback the database if needed. |