To be able to access an SQL table with a Natural program via Natural
SQL Gateway
Establish a connection to the ConnecX SQL Engine JDBC server.
Deploy a ConnecX SQL Engine data dictionary (CDD) containing the definition of the SQL table to be accessed.
If the table does not yet exists on the SQL database system, it can
be created with a CREATE TABLE statement.
If the table already exists, the table definition can be imported from the SQL catalog into the CDD, using the ConnecX
SQL Engine data dictionary manager. Keep in mind that the Import function of
the data dictionary manager creates the table definition with the qualifier
name dbo. This is usually undesired and can be easily reverted to the original qualifier by means of the Change Owner tool of the data
dictionary manager.
Invoke the Natural utility SYSDDM and enter function
code Z to create a Natural data definition module (DDM) describing
the SQL table.
In the NTDB
macro in the Natural parameter module NATPARM, define the DBID
of the DDM as database type SQL.
In the NDBID macro in the NDBPARM
module, define the DBID of the DDM as database type CNX. The SQL table to be
accessed has to be defined in the CDD, see also the ConnecX SQL
Engine Data Dictionary documentation.
Once you have defined a DDM for an SQL table, you can access the data stored in this table, using a Natural program.
Natural SQL Gateway translates the statements of a Natural program into SQL statements.
Natural SQL Gateway automatically provides for the preparation and execution of each statement in dynamic mode. Static execution is currently not supported. A statement is only prepared once (if possible) and can then be executed several times. For this purpose, Natural internally maintains a table of all prepared statements (see Statement Table in Internal Handling of Dynamic Statements).
Almost the full range of possibilities offered by the Natural programming language can be used for the development of Natural applications which access SQL tables. For a number of Natural DML statements, however, there are certain restrictions and differences as far as their use with SQL is concerned; see Using Natural DML Statements as described in Using Natural Statements and System Variables. In the Natural Statements documentation, you can find notes on Natural usage with SQL in the descriptions of the statements concerned.
Note:
As there is no SQL equivalent to Adabas Internal Sequence
Numbers (ISNs), any Natural features which use ISNs are not available when accessing
SQL tables with Natural.
In addition to the Natural DML statements, Natural provides SQL statements for SQL databases as discussed in Using Natural SQL Statements. In the section SQL Statements in the Natural Statements documentation, you can find detailed information on these statements.
