Kbase 15454: ESQL terminology and licensing explained for Versions 7 & 8
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/05/1998 |
|
ESQL terminology and licensing explained for Versions 7 & 8
The following summarizes terminology and licensing requirements
when using Embedded SQL ("Structured Query Language") on Version
7 and Version 8 PROGRESS. This summary does *not* apply to
Version 6.
SMALL CLIENT vs. LARGE CLIENT
-----------------------------
There are two architectures in Embedded SQL - small
client and large client. These are described in the ESQL
documentation. They differ in whre the SQL compilation
occurs. In the large client architecture, the PROGRESS
compiler code is bundled with the application (minimum
image size is 2Mb). The small client architecture uses
the Open Interface Driver (OID). The OID contains the
compiler code and is separable from the application code.
STATIC SQL vs. DYNAMIC SQL
--------------------------
There are two types of embedded SQL, static and dynamic.
In static embedded SQL, all data access is known and coded
at application development time. In dynamic embedded SQL,
none of the data access is known at application development
time - the queries are supplied by the user at runtime. The
application developer must get the queries from the user
and supply them to our embedded SQL product.
THE SQL PREPROCESSOR
--------------------
When building an ESQL application, you have the choice of
using the SQL Preprocessor or not (most people use it.)
Further, if you're doing static SQL, you have the choice
of running the preprocessor in what we call pre-compilation
mode. This mode causes the queries to be compiled at
application development time to remove the compilation
overhead when running the application.
LICENSING REQUIREMENTS
----------------------
For Large Client:
if database is local, you just need standalone db.
if database is remote, you need client networking.
For Small Client:
OID Location DB Location license needed
------------ ----------- --------------
local local standalone db
local remote client networking
remote N/A client networking
Using the SQL Preprocessor:
Regardless of precompilation - ESQL license.
If precompiling, it depends on where the database is.
The SQL Preprocessor is itself an Embedded SQL
application so the rules for it in precompilation
mode are the same for a regular ESQL large-client
application.
Progress Software Technical Support Note # 15454