DataFlex Wiki - User contributions [en]

Talk:AJAX - Return Arrays and Structs to your JavaScript with XML

2009-01-12T23:18:04Z

150.101.72.9: /* I believe using JSon is a much better match. */ new section

From Akennard:

I just wanted to ask 'why' this works ....

Get paXml of hoXml to aXml
Send Destroy of hoRoot
Send Destroy of hoXML
Function_Return aXML

End_Function

Is it because VDF does not ACTUALLY destroy and objects untill it gets to end_function ? because returning a handle to something you have just destroyed doesn't look quite right ? ie you are returning a handle to nothing or something that might still exist at that point ?
VDF has a special XmlHandle return type for returning a hoXML object and the tidying up after itself
Is there a reason why this has not been used in this case ? eg would this work for AJAX ?

{ Published = True }
{ Description = "" }

Function NameCasing String sName Returns XMLHandle

Handle hoRoot hoXML hoEvent
Address aXml
// create xml document

Get Create U_cXMLDOMDocument to hoXML
Set pbValidateOnParse of hoXML to False
Get CreateDocumentElement of hoXML "response" to hoRoot
Send AddElement of hoRoot "lowercase" (lowercase(sName))
Send AddElement of hoRoot "uppercase" (Uppercase(sName))
Send AddElement of hoRoot "propercase" (Uppercase(Left(sName,1))+lowercase(Right(sName,(length(sName)-1))))
Function_Return hoXML // runtime will transfer and then destroy this object because of XMLHandle return type

End_Function // NameChanges

== I believe using JSon is a much better match. ==

We have been using JSON to move VDF Structs to Javascript.
This is I believe a much nicer and simpler way (and definately faster).
We did one test of all customers, with all orders, with all orderlines, from VDF to ASP. On this particular laptop using VDF took 40 seconds, sending the same data using JSon it took 1.2 seconds...

Anyway, no time now to update an article, but just wanted to point this out.

Portal:Data Connectivity

2008-02-19T10:14:43Z

150.101.72.9: /* Recent Additions */

The '''Data Dictionaries Portal''' contains a series of articles related to using the [[DataDictionary]] class. These classes often span development in both [[DataFlex|Character Mode]], [[Visual DataFlex]] and [[Web Application|Web Applications]].

==Recent Additions==
*What is a [[Data Dictionary]]?

==Tutorials==

==Requested Articles==

[[Category:Portals]]
[[Category:Data Dictionaries]]

South Australia DataFlex Users Group

2008-02-19T10:05:53Z

150.101.72.9: Redirecting to South Australia Dataflex Users Group

#REDIRECT [[South Australia Dataflex Users Group]]

Data Dictionaries

2007-11-29T07:20:50Z

150.101.72.9:

'''Data Dictionaries''' are a class layer between your application and the database tables. They are considered to be a vital part of any Dataflex development.

The [[Database Builder]] tool helps you defining the class with visual aid for:
*Field settings like ''Capslock''
*Table settings like calculations on save or save/delete validations
*Relationship settings like [[Cascade Delete]].

The Datadictionary class can also contain and business rules required when records are created, edited or deleted.

==How to create a new Data Dictionary from scratch==

#Open [[Database Builder]].
#Create a new table
#Enter some columns (input name, type and width)
#Choose '''Maintenance''' and '''Create Empty DataDictionary'''.

NOTE: remember to enter a width for your column.

==How to create Relationships==

Before creating relationships, make sure that both tables should have an index.
*use 'the relationship wizard' in the database builder.

== Use Data Dictionaries in Batch Processes ==
When using the studio, the usage of Data Dictionaries are very naturally integrated into your project. But when doing a save without dbForm objects eg in a batch process or so, a lot of developers are going back to the file buffer way. This way it bypasses the class structure you carefully put in place for saves, deletes, updates etc.
Please check [[Using Data Dictionaries in Business Processes]] for help and sample code.

=Supported backends=

It is possible to reach several databases through the Data Access [[DataFlex Connectivity Kit]] or using third party
drivers from Mertech Data [http://mertechdata.com/rainbow/site/1/default.aspx]

*Native Dataflex database
*[[Oracle]] [http://wiki.oracle.com/page/Database]
*[[Microsoft SQL Server]] [http://msdn2.microsoft.com/en-us/sql/default.aspx]
*[[Pervasive]] [[SQL]]
*[[ODBC]]
*[[MySQL]]
*[[IBM DB2]]

[[Category:Basics]]

IBM DB2

2007-11-29T07:15:27Z

150.101.72.9:

For many years IBM DB2 was exclusive to the very expensive Mainframes and other heavy servers, and the only connnectivity from DataFlex was for minor applications.

Nowadays IBM DB2 UDB has a free version for use in commercial environments. It is the Express-C[http://www-306.ibm.com/software/data/db2/express/] edition.

The great things about this database are:
#Its free, with unlimited database size (but server memory <= 4Gb)
#DB2 server runs on Windows but also Linux and many others
#The DB2 data can be accessed from [[DF32]] Linux programs as well as VDF and other programmnig environments
#It is really fast and self tuning, no DBA hours required
#[[Data Access]] And [[Mertech Data]] have fantastic Connectivity Kits, not only from VDF but also from Linux DataFlex Console Mode systems.

== Running Character Mode DF32 ==

If you still have a lot of *[[DataFlex| Character mode]] programming. And it is not an option to move to VDF (Because of bandwith, factory environment, etc), I recommend that you have a serious look at:
*Convert your Console Mode program to Linux
*Convert your DataFlex tables to DB2

This opens up a new world for unleashing your data in a safe way. You can do datamining, run crystal without DataFlex CK, even create Java, .Net or any other applications all using your data. Offcourse this does not take [[Data Dictionaries]] into effect, but you most likely did not have these anyway in [[DF32]].

== Conversion ==

The conversion from Embedded DataFlex to DB2 has some gotcha's;
*DB2 has several options for Collating Sequence. Please carefully select this prior to creating your database matching with your collate.cfg. (Hint: use 'Fill_Field' rather than move 'zzzz' in your old programs), or use the DAW utility CreaDb to create the database matching the Collate.cfg.
*Some nested reports might run slower. Concider creating an SQL View, link this as a table using the Filelist and a INT file, then report from the 'Flat file'.

IBM DB2

2007-11-29T07:13:46Z

150.101.72.9:

For many years IBM DB2 was exclusive to the very expensive Mainframes and other heavy servers, and the only connnectivity from DataFlex was for minor applications.

Nowadays IBM DB2 UDB has a free version for use in commercial environments. It is the Express-C[http://www-306.ibm.com/software/data/db2/express/] edition.

The great things about this database are:
#Its free, with unlimited database size (but server memory <= 4Gb)
#DB2 server runs on Windows but also Linux and many others
#The DB2 data can be accessed from [[DF32]] Linux programs as well as VDF and other programmnig environments
#It is really fast and self tuning, no DBA hours required
#[[Data Access]] And [[Mertech Data]] have fantastic Connectivity Kits, not only from VDF but also from Linux DataFlex Console Mode systems.

== Running Character Mode DF32 ==

If you still have a lot of *[[DataFlex| Character mode]] programming. And it is not an option to move to VDF (Because of bandwith, factory environment, etc), I recommend that you have a serious look at:
*Convert your Console Mode program to Linux
*Convert your DataFlex tables to DB2

This opens up a new world for unleashing your data in a safe way. You can do datamining, run crystal without DataFlex CK, even create Java, .Net or any other applications all using your data. Offcourse this does not take [[Data Dictionaries]] into effect, but you most likely did not have these anyway in [[DF32]].

== Conversion ==

The conversion from Embedded DataFlex to DB2 has some gotcha's;
*DB2 has several options for Collating Sequence. Please carefully select this prior to creating your database matching with your collate.cfg. (Hint: use 'Fill_Field' rather than move 'zzzz' in your old programs)
*Some nested reports might run slower. Concider creating an SQL View, link this as a table using the Filelist and a INT file, then report from the 'Flat file'.

IBM DB2

2007-11-29T03:50:50Z

150.101.72.9: Better link for Express-C download

For many years IBM DB2 was exclusive to the very expensive Mainframes and other heavy servers, and the only connnectivity from DataFlex was for minor applications.

Nowadays IBM DB2 UDB has a free version for use in commercial environments. It is the Express-C[http://www.ibm.com/developerworks/downloads/im/udbexp/] edition.

The great things about this database are:
#Its free, with unlimited database size (but server memory <= 4Gb)
#DB2 server runs on Windows but also Linux and many others
#The DB2 data can be accessed from [[DF32]] Linux programs as well as VDF and other programmnig environments
#It is really fast and self tuning, no DBA hours required
#[[Data Access]] And [[Mertech Data]] have fantastic Connectivity Kits, not only from VDF but also from Linux DataFlex Console Mode systems.

== Running Character Mode DF32 ==

If you still have a lot of *[[DataFlex| Character mode]] programming. And it is not an option to move to VDF (Because of bandwith, factory environment, etc), I recommend that you have a serious look at:
*Convert your Console Mode program to Linux
*Convert your DataFlex tables to DB2

This opens up a new world for unleashing your data in a safe way. You can do datamining, run crystal without DataFlex CK, even create Java, .Net or any other applications all using your data. Offcourse this does not take [[Data Dictionaries]] into effect, but you most likely did not have these anyway in [[DF32]].

== Conversion ==

The conversion from Embedded DataFlex to DB2 has some gotcha's;
*DB2 has several options for Collating Sequence. Please carefully select this prior to creating your database matching with your collate.cfg. (Hint: use 'Fill_Field' rather than move 'zzzz' in your old programs)
*Some nested reports might run slower. Concider creating an SQL View, link this as a table using the Filelist and a INT file, then report from the 'Flat file'.

IBM DB2

2007-11-29T03:43:54Z

150.101.72.9:

For many years IBM DB2 was exclusive to the very expensive Mainframes and other heavy servers, and the only connnectivity from DataFlex was for minor applications.

Nowadays IBM DB2 UDB has a free version for use in commercial environments. It is the Express-C[http://www-306.ibm.com/software/data/db2/9/edition-express-c.html] edition.

The great things about this database are:
#Its free, with unlimited database size (but server memory <= 4Gb)
#DB2 server runs on Windows but also Linux and many others
#The DB2 data can be accessed from [[DF32]] Linux programs as well as VDF and other programmnig environments
#It is really fast and self tuning, no DBA hours required
#[[Data Access]] And [[Mertech Data]] have fantastic Connectivity Kits, not only from VDF but also from Linux DataFlex Console Mode systems.

== Running Character Mode DF32 ==

If you still have a lot of *[[DataFlex| Character mode]] programming. And it is not an option to move to VDF (Because of bandwith, factory environment, etc), I recommend that you have a serious look at:
*Convert your Console Mode program to Linux
*Convert your DataFlex tables to DB2

This opens up a new world for unleashing your data in a safe way. You can do datamining, run crystal without DataFlex CK, even create Java, .Net or any other applications all using your data. Offcourse this does not take [[Data Dictionaries]] into effect, but you most likely did not have these anyway in [[DF32]].

== Conversion ==

The conversion from Embedded DataFlex to DB2 has some gotcha's;
*DB2 has several options for Collating Sequence. Please carefully select this prior to creating your database matching with your collate.cfg. (Hint: use 'Fill_Field' rather than move 'zzzz' in your old programs)
*Some nested reports might run slower. Concider creating an SQL View, link this as a table using the Filelist and a INT file, then report from the 'Flat file'.

Data Dictionaries

2007-11-26T02:12:42Z

150.101.72.9: /* Supported backends */

'''Data Dictionaries''' are a class layer between your application and the database tables. They are considered to be a vital part of any Dataflex development.

The [[Database Builder]] tool helps you defining the class with visual aid for:
*Field settings like ''Capslock''
*Table settings like calculations on save or save/delete validations
*Relationship settings like [[Cascade Delete]].

The Datadictionary class can also contain and business rules required when records are created, edited or deleted.

==How to create a new Data Dictionary from scratch==

#Open [[Database Builder]].
#Create a new table
#Enter some columns (input name, type and width)
#Choose '''Maintenance''' and '''Create Empty DataDictionary'''.

NOTE: remember to enter a width for your column.

==How to create Relationships==

Before creating relationships, make sure that both tables should have an index.
*use 'the relationship wizard' in the database builder.

=Supported backends=

It is possible to reach several databases through the Data Access [[DataFlex Connectivity Kit]] or using third party
drivers from Mertech Data [http://mertechdata.com/rainbow/site/1/default.aspx]

*Native Dataflex database
*[[Oracle]] [http://wiki.oracle.com/page/Database]
*[[Microsoft SQL Server]] [http://msdn2.microsoft.com/en-us/sql/default.aspx]
*[[Pervasive]] [[SQL]]
*[[ODBC]]
*[[MySQL]]
*[[IBM DB2]]

[[Category:Basics]]