Dameng

This documentation is valid for:
GeneXus 18 Help
GeneXus 17 Help

Dameng Database is a professional database products provider and technology service.

Here you will not get detailed information about this DBMS, check the manufacturer for more detail. However, it is a brief usage introduction from the GeneXus perspective.

At least you need to configure the following properties to get started:

Supported DM 8.0 and above; just prototype as usual.

Considerations

Available for the GeneXus Java generator.
Geodatabase functionality is not supported by the DBMS.
The Enable connection pooling property in false is not supported.
The preview of Query and Dashboard objects will display sample data.
Database Reverse Engineering not supported yet.

Reserved Words

The following list of escaped words by GeneXus when reorganizing are:

USER
UPDATE
DEFAULT
DESC
LEVEL
SESSION
ORDER

Check the list of reserved words, the following error may appear when reorganizing

dm.jdbc.driver.DMException: line X, column Y, nearby [SomeReservedWord] has error:
Syntax error

Useful Information

Some useful SQL commands to interect with the DBMS. Once the software is installed the default super-user is SYSDBA.

User Manipulation

To create a user and generic user manipulation:

# Create a user
CREATE USER name IDENTIFIED BY pwd
GRANT RESOURCE TO name
# Delete a user
DROP USER name CASCADE

Each user has a default schema with the same name. To access tables, views, etc. in its own schema, it is not necessary to add a schema name. To access objects in other schemas, a schema name is required; use the Schema Name Property.

# Create a schema
CREATE SCHEMA name AUTHORIZATION SYSDBA;
# Drop a schema
DROP SCHEMA name CASCADE;

Data Manipulation

A couple of standard SQL DML sentences:

SELECT * FROM tablename
INSERT INTO tablename(att1, att2) VALUES(1, 'one')
TRUNCATE TABLE tablename
DROP TABLE tablename CASCADE CONSTRAINTS

General

A couple of queries to get parameters, connections and related information from the database.

# Configuration
SELECT * FROM SYS."V$VERSION"
SELECT * FROM SYS."V$DATABASE"
SELECT * FROM SYS."V$INSTANCE"
SELECT * FROM SYS."V$DM_INI" WHERE PARA_NAME LIKE '%SomeFilter%'
SELECT * FROM SYS."V$PARAMETER" WHERE NAME LIKE '%SomeFilter%'
# Connections
SELECT * FROM SYS."V$CONNECT"
SELECT * FROM V$SESSIONS
# Close a connection
call sp_close_session (SESSIONID);

Availability

This property is available since GeneXus 17 Upgrade 11.