[Info-vax] Calling $CREPRC in COBOL

[Richard Maher]

On 11/07/2022 7:57 am, VAXman- at SendSpamHere.ORG wrote:
> In article <62ca1a22$0$707$14726298 at news.sunsite.dk>,
> =?UTF-8?Q?Arne_Vajh=c3=b8j?= <arne at vajhoej.dk> writes:
>> On 7/9/2022 8:06 PM, Arne Vajhøj wrote:
>>> On 7/4/2022 10:34 AM, seasoned_geek wrote:
>>>> On Sunday, July 3, 2022 at 7:22:57 PM UTC-5, Arne Vajhøj
>>>> wrote:
>>>>> On 7/3/2022 4:05 PM, seasoned_geek wrote:
>>>>>> On Thursday, June 23, 2022 at 9:14:07 AM UTC-5,
>>>>>> osuv... at gmail.com wrote:
>>>>>>> On Tuesday, June 21, 2022 at 12:08:21 AM UTC-4, Dave
>>>>>>> Froble wrote:
>>>>>> At any rate, there is no SQL that will let you put
>>>>>> multi-typed records in a table. The "best" you could hope
>>>>>> for is to have the primary key fields then a BLOB object
>>>>>> one had to hack like we did in BASIC. You would be right
>>>>>> back to CVT$% 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
> 
> ... and here I thought that barely a read-only lingo COBOL was
> verbose.
> 
> I still remember when comp.os.vms would see actual "code" posted to
> it.
> 

No, you invent LINQ so you can load all the data into Collections in 
memory and forget about RELATIONAL data structures and SQL. Also must 
forget that all RDBMS' have lovely query optimizers and Stored 
Procedures for definer's rights execution.

But I only want one column from that table. NO you must return all of 
the class properties and forget about aggregate functions etc