[Info-vax] Calling $CREPRC in COBOL

[Richard Maher]

On 10/07/2022 8:15 am, Arne Vajhøj wrote:
> On 7/9/2022 8:06 PM, Arne Vajhøj wrote:
>> On 7/4/2022 10:34 AM, seasoned_geek wrote:
>>> On Sunday, July 3, 2022 at 7:22:57 PM UTC-5, Arne Vajhøj wrote:
>>>> On 7/3/2022 4:05 PM, seasoned_geek wrote:
>>>>> On Thursday, June 23, 2022 at 9:14:07 AM UTC-5,
>>>>> osuv... at gmail.com wrote:
>>>>>> On Tuesday, June 21, 2022 at 12:08:21 AM UTC-4, Dave Froble
>>>>>> wrote:
>>>>> At any rate, there is no SQL that will let you put
>>>>> multi-typed records in a table. The "best" you could hope for
>>>>> is to have the primary key fields then a BLOB object one had
>>>>> to hack like we did in BASIC. You would be right back to
>>>>> CVT$% and RSET logic. (Didn't they drop RSET and LSET from
>>>>> the DEC BASIC specification at some point?)
>>>> Not true.
>>>> 
>>>> You define a super class and sub classes and your ORM
>>>> framework transparently stores and retrieved the different
>>>> classes.
>>>> 
>>>> That is basic persistence knowledge. Any young developer would 
>>>> know that.
>>> 
>>> Well, we will ask Dave to post the TOLAS invoice (or order)
>>> record layouts for a defunct customer and you create a
>>> functioning VAX BASIC program using SQLite along with Superclass 
>>> and Subclass and post it here.
>> 
>> It is techniques used by hundreds of thousands maybe millions of 
>> applications.
>> 
>> VMS Basic would be a problem as I am not aware of any ORM framework
>> for VMS Basic.
>> 
>> (and I also suspect that VMS Basic would need some new features to
>> be able to create a good one)
> 
> But let me show something. Not TOLAS - just hello world level.
> 
> Obvious choices would be Java + Hibernate, C# + Entity Framework or
> PHP + Doctrine, but since Groovy and Basic are part of the thread
> then Groovy + Hibernate and VB.NET + Entity Framework.
> 
> Database definition and a few rows:
> 
> CREATE TABLE p ( id INTEGER NOT NULL, typ INTEGER NOT NULL, PRIMARY
> KEY(id) ); CREATE TABLE c1 ( id INETGER NOT NULL, ival INTEGER, 
> PRIMARY KEY(id) ); CREATE TABLE c2 ( id INETGER NOT NULL, sval
> VARCHAR(50), PRIMARY KEY(id) ); INSERT INTO p VALUES(1, 1); INSERT
> INTO c1 VALUES(1, 123); INSERT INTO p VALUES(2, 2); INSERT INTO c2
> VALUES(2, 'ABC');
> 
> First Groovy + Hibernate.
> 
> What is needed: * Java * Groovy * Hibernate * SQLite dialect for
> Hibernate version * JDBC driver for SQLite
> 
> Data classes:
> 
> package mt
> 
> import javax.persistence.*
> 
> // parent class @Entity
> @Inheritance(strategy=InheritanceType.JOINED) class P { @Id int id 
> int typ }
> 
> // child class 1 @Entity @PrimaryKeyJoinColumn(name="id") class C1
> extends P { @Id int id int ival @Override String toString() { return
> "C1: $id -> $ival" } }
> 
> // child class 2 @Entity @PrimaryKeyJoinColumn(name="id") class C2
> extends P { @Id int id String sval @Override String toString() { 
> return "C2: $id -> $sval" } }
> 
> Config file with database connection:
> 
> <persistence xmlns="http://java.sun.com/xml/ns/persistence" 
> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
> xsi:schemaLocation="http://java.sun.com/xml/ns/persistence 
> http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" 
> version="2.0"> <persistence-unit name="testdb"> 
> <provider>org.hibernate.ejb.HibernatePersistence</provider> 
> <class>mt.P</class> <class>mt.C1</class> <class>mt.C2</class> 
> <exclude-unlisted-classes/> <properties> <!--<property
> name="show_sql" value="true"/>--> <property
> name="hibernate.connection.driver_class" value="org.sqlite.JDBC"/> 
> <property name="hibernate.connection.url" 
> value="jdbc:sqlite:test.db"/> <property
> name="hibernate.connection.username" value=""/> <property
> name="hibernate.connection.password" value=""/> <property
> name="hibernate.dialect" 
> value="org.sqlite.hibernate.dialect.SQLiteDialect"/> </properties> 
> </persistence-unit> </persistence>
> 
> And it is all ready.
> 
> Demo:
> 
> package mt
> 
> import java.util.logging.*
> 
> import javax.persistence.*
> 
> // disable logging 
> Logger.getLogger("org.hibernate").setLevel(Level.OFF) // open
> connection emf = Persistence.createEntityManagerFactory("testdb") em
> = emf.createEntityManager() // add a C1 and C2 
> em.getTransaction().begin() em.persist(new C1(id:3, typ:1,
> ival:456)) em.persist(new C2(id:4, typ:2, sval:"DEF")) 
> em.getTransaction().commit() // find by PK println(em.find(P.class,
> 2)) // list all for(o in em.createQuery("SELECT o FROM P AS o",
> P.class).getResultList()) { println("${o}") } // list all C2 for(o in
> em.createQuery("SELECT o FROM C2 AS o", P.class).getResultList()) { 
> println("${o}") } // list some for(o in em.createQuery("SELECT o FROM
> P AS o WHERE o.id BETWEEN 2 and 3", P.class).getResultList()) { 
> println("${o}") } // close connection em.close() emf.close()
> 
> Note that: this should run on VMS Itanium as all the pieces needed
> are available.
> 
> Now VB.NET + Entity Framework.
> 
> What is needed: * .NET * Entity Framework * ADO.NET provider for
> SQLite (includes Entity Framework support)
> 
> Data classes:
> 
> Imports System Imports System.ComponentModel.DataAnnotations Imports
> System.ComponentModel.DataAnnotations.Schema Imports
> System.Data.Entity
> 
> Namespace MT ' parent class <Table("P")> Public Class P <Key>
> <DatabaseGenerated(DatabaseGeneratedOption.None)> Public Property
> Id() As Integer Public Property Typ() As Integer End Class ' child
> class 1 <Table("C1")> Public Class C1 Inherits P Public Property
> Ival() As Integer Public Overrides Function ToString() As String 
> Return $"C1: {id} -> {ival}" End Function End Class ' child class 2 
> <Table("C2")> Public Class C2 Inherits P Public Property Sval() As
> String Public Overrides Function ToString() As String Return $"C2:
> {id} -> {sval}" End Function End Class ' database context Public
> Class TestDbContext Inherits DbContext Public Sub New(constrkey As
> String) MyBase.New(constrkey) End Sub Public Property P() As DbSet(Of
> P) Public Property C1() As DbSet(Of C1) Public Property C2() As
> DbSet(Of C2) End Class End Namespace
> 
> Config file with database connection:
> 
> <?xml version="1.0" encoding="utf-8"?> <configuration> 
> <configSections> <section name="entityFramework" 
> type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection,
>  EntityFramework" requirePermission="false" /> </configSections> 
> <connectionStrings> <add name="TestDB" connectionString="Data
> Source=.\test.db" providerName="System.Data.SQLite"/> 
> </connectionStrings> <entityFramework> <providers> <provider
> invariantName="System.Data.SQLite" 
> type="System.Data.SQLite.EF6.SQLiteProviderServices, 
> System.Data.SQLite.EF6"/> <provider
> invariantName="System.Data.SQLite.EF6" 
> type="System.Data.SQLite.EF6.SQLiteProviderServices, 
> System.Data.SQLite.EF6"/> </providers> </entityFramework> <startup> 
> <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.1"
> /> </startup> <system.data> <DbProviderFactories> <remove
> invariant="System.Data.SQLite" /> <remove
> invariant="System.Data.SQLite.EF6" /> <add name="SQLite Data Provider
> (Entity Framework 6)" invariant="System.Data.SQLite.EF6"
> description=".NET Framework Data Provider for SQLite (Entity
> Framework 6)" type="System.Data.SQLite.EF6.SQLiteProviderFactory, 
> System.Data.SQLite.EF6" /> <add name="SQLite Data Provider" 
> invariant="System.Data.SQLite" description=".NET Framework Data
> Provider for SQLite" type="System.Data.SQLite.SQLiteFactory,
> System.Data.SQLite" /> </DbProviderFactories> </system.data> 
> </configuration>
> 
> And it is all ready.
> 
> Demo:
> 
> Imports System Imports System.Data.Entity Imports System.Linq
> 
> Namespace MT Public Class Program Public Shared Sub Main(args As
> String()) ' open and close connection Using ctx As TestDbContext =
> new TestDbContext("TestDB") ' add a C1 and C2 ctx.P.Add(New C1 With {
> .Id = 3, .Typ = 1, .Ival = 456 }) ctx.P.Add(New C2 With { .Id = 4,
> .Typ = 2, .Sval = "DEF" }) ctx.SaveChanges ' find by PK 
> Console.WriteLine((From o In Ctx.P Where o.Id = 2 Select
> o).FirstOrdefault) ' list all For Each ox In (From o In Ctx.P Select
> o) Console.WriteLine(ox) Next ' list all C2 For Each ox In (From o In
> Ctx.C2 Select o) Console.WriteLine(ox) Next ' list some For Each ox
> In (From o In Ctx.P Where 2 <= o.Id  And o.Id <= 3 Select o) 
> Console.WriteLine(ox) Next End Using End Sub End Class End Namespace
> 
> Arne
> 
> 

Why do OO programmers refuse to use SQL :-(

A TABLE <> CLASS!!!

ORMs are just another abstraction for abstraction's sake.