How translation works

What happens in the database when you translate. Applies to iDempiere 11 and later. Checked against iDempiere master in October 2026.

In short

• Each translatable table has a _Trl twin with one row per language.
• IsTranslated is a status flag. N marks a row for review: often it still holds the English copy, but it can also hold an older translation.
• Editing English text, Synchronize Terminology and Synchronize Doc Translation can overwrite translations.

Tables

AD_Message has AD_Message_Trl, M_Product has M_Product_Trl, and so on. A _Trl row holds:

• the key of the base record and AD_Language
• a copy of each column marked Translated. To add a _Trl table to your own table, see Create/Complete Table.
• IsTranslated
• a UU column, for example AD_Message_Trl_UU

AD_Message_Trl also has AD_Client_ID in its key, for tenant-level messages.

Language flags

Flag	Meaning
Base Language	Language of the base tables. en_US by default.
System Language	iDempiere keeps _Trl rows for it.
Login Locale	Users can pick it on the login page.

When rows are created

• New record: one _Trl row per system language, copied from the base text (PO.insertTranslations()).
• New language: only when you run Language Maintenance with Add.
• Upgrade: SyncDB adds missing rows, then runs Synchronize Terminology.

When rows are updated

Editing a translated column of a base record (PO.updateTranslations()):

Multi Lingual Documents	Result
Off	All languages get the new text. Translations are lost.
On, Tenant language = base language	Texts stay. All rows marked IsTranslated='N'.
On, Tenant language ≠ base language	Tenant language gets the new text. Other languages get IsTranslated='N'.

A migration script that changes English text with SQL changes no _Trl row and flags nothing.

System Administrator edits dictionary texts in the "System" Tenant, so that Tenant's Multi Lingual Documents setting decides what happens to dictionary translations. Check it in the Tenant window before you edit English texts. The default in a new database has not been verified.

Processes

Process	Effect
Language Maintenance	Add, delete or re-create the rows of one language
Synchronize Terminology	Copies element translations to fields, parameters, print format items, menus. Overwrites.
Synchronize Doc Translation	Copies base text into non-AD _Trl tables (products, mail templates). Overwrites.
Translation Import/Export	Exports to XML, or updates rows from XML. See Ship translations.

None of them resets the cache. Run Cache Reset afterwards.

Log Migration Scripts never logs _Trl changes.

Translated views

A view <name>_v can have a twin <name>_vt that joins the _Trl tables and has an AD_Language column, for example C_Invoice_Header_v and C_Invoice_Header_vt. When the language is not the base language, iDempiere reads the _vt view instead and filters on the language:

Reader	Switches to _vt when	Language
Built-in print format	the _vt view exists in the database	The printout language
REST API (/api/v1/models/<name>_v)	the _vt view is registered as a table in the Application Dictionary	The language given at login
Jasper report	never, the report's SQL must query _vt itself	CURRENT_LANG

The caller always asks for _v and gets translated data.

For your own _vt view:

• Give it the same columns as the _v view, plus AD_Language.
• Join each _Trl table on the language. A join without it returns every row once per language.
• Register it in the Application Dictionary if the REST API should use it.

Measure the coverage of a language

PostgreSQL and Oracle:

SELECT t, AD_Language, COUNT(*) AS total,
  SUM(CASE WHEN IsTranslated='Y' THEN 1 ELSE 0 END) AS translated
FROM (
  SELECT 'AD_Message' AS t, AD_Language, IsTranslated FROM AD_Message_Trl WHERE AD_Client_ID=0
  UNION ALL SELECT 'AD_Element', AD_Language, IsTranslated FROM AD_Element_Trl
  UNION ALL SELECT 'AD_Field', AD_Language, IsTranslated FROM AD_Field_Trl
  UNION ALL SELECT 'AD_Menu', AD_Language, IsTranslated FROM AD_Menu_Trl
) x
GROUP BY t, AD_Language
ORDER BY t, AD_Language;

The result is only as good as the flags the language pack set.