Metodologia de sqlrdd

Implementing SQLRDD

Why should you migrate to SQL ?
Security Physical integrity Logical application integrity (transactional control) Speed should not be the main reason!

First, let’s say itcorrectly...
file, database Field Record Directory TABLE COLUMN LINE DATABASE

DML – Data manipulation language (seek, replace, skip, etc..) DDL – Data definition language (dbCreate(), INDEX,etc.)

SQLRDD layers
Your Application SQL Parser Connection Classes
MySQL Postgres Firebird Oracle Microsoft Caché ADABAS Sybase IBM What’s Next ?

RDD

Direct Access

RDD (ReplaceableDatabase Driver)
DBFCDX compatible DDL and DML support Translate xBase (ISAM) to SQL
Cache Workareas Paging Workareas

Connect to databases through “Connection Classes”

Connection Classes
Ensembleof classes that provides database access Direct record set manipulation Provides direct database access to applications, but with database’s suitable SQL dialect (not portable)

SQL Parser
Providesa “natural”, database independent SQL language Compiles the natural SQL and generates an SQL pCode Generates database specific SQL code based in SQL pCode Processes only DML at this time (SELECT,INSERT, UPDATE, DELETE)

SQL Parser / Code Generator
Oracle pCode
SELECT A."id", B."descr" FROM tab1 A, tab2 B WHERE A."id" = B."id" (+) AND A."date" = TO_DATE('20021231','YY YYMMDD')

MicrosoftProgramming Language SQLRDD JIT Compiler Run Time Code Generator DB/2

SELECT A.[id], B.[descr] FROM tab1 A WITH (NOLOCK), tab2 B WITH (NOLOCK) WHERE A.[id] *= B.[id] AND A.[date] = '20021231'etc.. Select a.id, b.descr from tab1 a, tab2 b where a.id left outer join b.id and a.date = [20021231]
SELECT tab1."id", tab2."descr" FROM tab1 LEF OUTER JOIN tab2 ON tab1."id" = tab2."id" WHEREatb1."date" = '2002-12-31'

What’s Next ?

Differentials
Only tool in the market that allows real portability to many different databases (it has no similar in any other language) Does not need any...