Welcome
Developing
Developing EGL applications
Enterprise Generation Language (EGL) is a programming language that you can use to focus on business problems instead of software technologies. Within the Rational® development environment, you can use EGL wizards and other tools to write complex applications with minimal effort.
EGL Language Reference
The EGL Language Reference covers the fundamental use of the language, including its concepts, syntax, and keywords. This volume is intended for a developer writing EGL applications with some experience in procedural programming.
Accessing data in EGL
Whenever you access a data store in EGL, the data goes into a record.
SQL data access
EGL supports relational database access through SQL.
SQL record internals

Overview
Getting started
Installing
Upgrading and migrating
EGL Code Accelerator for IBD
Developing
- Model driven development of EGL code
- Generating source code from UML models
  You can use transformations to create source code from a UML model. First you must create a transformation parameters file and then apply those parameters to a model.
- Generating the EGL Dependency Graph from EGL projects
- Generating Source Code from OpenAPI Documents
- Developing EGL applications
  Enterprise Generation Language (EGL) is a programming language that you can use to focus on business problems instead of software technologies. Within the Rational® development environment, you can use EGL wizards and other tools to write complex applications with minimal effort.
  - How to use this documentation
  - Additional information about EGL
    The most recent EGL documentation is in the IBM Business Developer documentation.
  - EGL Programmer's Guide
    The EGL Programmer's Guide covers using EGL within the Eclipse Integrated Development Environment (IDE), as well as some of the common programming tasks that EGL developers perform.
  - EGL Generation Guide
    The EGL Generation Guide covers the process of converting EGL code to Java™ or COBOL source code, including the processes and the files involved. This section is intended for a developer who will generate or deploy EGL applications.
  - EGL Language Reference
    The EGL Language Reference covers the fundamental use of the language, including its concepts, syntax, and keywords. This volume is intended for a developer writing EGL applications with some experience in procedural programming.
    - General syntax
    - System data parts
    - User-defined data parts
    - Logic parts
    - Correspondence between a JSON string and an EGL variable
      This topic describes the EGL record that corresponds to a JavaScript™ Object Notation (JSON) string. Other topics describe the functions (serviceLib.convertFromJSON() and serviceLib.convertToJSON()) that are used by a Rich UI developer to convert JSON data to or from a variable, as may be necessary to access a third-party REST service. A failure in either function causes a RuntimeException.
    - Correspondence between a JSON string and an EGL variable for zOS and IBM i
      This topic describes the EGL record that corresponds to a JavaScript Object Notation (JSON) string. This topic describes the functions—serviceLib.convertFromJSON() and serviceLib.convertToJSON()—that are used by an EGL developer to convert JSON data to or from a variable either for zOS or IBM i systems. A failure in either function causes a RuntimeException.
    - Special considerations for JSON support on IBM i:
    - Correspondence between an XML string and an EGL variable
      This topic describes the EGL record that corresponds to an Extensible Markup Language (XML) string. Other topics describe the functions (serviceLib.convertFromXML and serviceLib.convertToXML) that are used by a Rich UI developer to convert XML data to or from a variable, as may be necessary to access a third-party REST service.
    - EGL statements
    - EGL core system libraries and variables
    - Accessing data in EGL
      Whenever you access a data store in EGL, the data goes into a record.
      - resourceAssociation variable for file I/O
        When your program uses a record in an I/O operation, EGL assumes that the record-specific recordName.resourceAssociation variable contains the name of the physical file that holds the record (if that variable supports the particular type of file).
      - Logical unit of work
      - Data access statements
        EGL data access statements perform the essential create, read, update, and delete (CRUD) functions for a data source.
      - execute considerations for CICS®
        In the context of CICS®, the EGL execute statement is typically used to carry out a native EXEC CICS statement with dynamic elements. Local EGL variables in the same program may be referenced in the statement, or labels within the same function. EGL will generate an EXEC CICS statement containing the provided text, resolved variable and label names and imbed this into the application program.
      - execute Considerations for COBOL
        In the context of COBOL, the EGL execute statement is typically used to carry out a native COBOL statement with dynamic elements. Local EGL variables in the same program may be referenced in the statement, or labels within the same function. EGL will generate a COBOL statement containing the provided text, resolved variable and label names and embed this into the application program.
      - Data access technologies
      - SQL data access
        EGL supports relational database access through SQL.
        Host variables
        Host variables allow SQL statements to use EGL variables.
        SQLRecord stereotype
        The SQLRecord stereotype specializes a Record part for use with a relational database.
        SQL record internals
        Logical expressions for SQL records
        SQLRecord field level properties
        Exception record for SQL
        EGL defines a specific Exception record for SQL access.
        sqlNullable
        sql directive
        Use the sql directive to customize implicit SQL code, or to write entirely new code.
        #sqlCondition directive
        The #sqlCondition directive lists conditions for an SQL SELECT statement.
        add considerations for SQL
        In the context of the SQL query language, the add statement adds a record or set of records to a database.
        close considerations for SQL
        delete considerations for SQL
        execute considerations for SQL
        In the context of SQL, the EGL execute statement is typically used to carry out a prepared SQL statement with dynamic elements.
        forEach considerations for SQL
        freeSQL
        get considerations for SQL
        In the context of SQL, the get statement retrieves record data from a result set.
        open considerations for SQL
        In the context of SQL, the EGL open statement creates a result set from a relational database and creates a cursor that you can use to move through the list.
        prepare considerations for SQL
        replace considerations for SQL
        set considerations for SQL
        get diagnostics considerations for SQL
        In the context of the SQL query language, you can use the get diagnostics statement to handle multiple SQL Errors.
        EGL library sqlLib
        Additional properties for programs using an SQL database
        Sample EGL SQL program
      - Data access using PSBs and PCBs
        Use program specification blocks (PSBs) and program communication blocks (PCBs) to describe the logical structures in a program you generate for COBOL.
      - DL/I database support
        EGL supports DL/I (Data Language/I), a hierarchical database manager for COBOL environments.
      - File I/O
        You can use EGL to read from or write to files directly, without using a database manager.
      - GSAM and IMS™ message queue access
        GSAM and IMS™ message queues are two examples of serial file access through EGL.
      - WebSphere® MQ message queue access
        EGL supports access of WebSphere® MQ (formerly MQSeries®) message queues on any of the target platforms.
      - iSeries® object access
        EGL provides a library and Record definitions to communicate with data queues and data areas on the iSeries®.
    - Applications with user interfaces
    - VisualAge® Generator compatibility
    - Appendices
    - Importing product-supplied projects
      You can click a link to download the current version of Rich UI projects. The capability is useful if you deleted a project or want a clean version.
  - Rational® COBOL Runtime Guide for zSeries®
    This manual provides information about customizing and administering the IBM® Rational® COBOL Runtime.
  - IBM Business Developer EGL Server Guide for IBM® i
    This manual provides information about customizing and administering EGL Server for IBM® i on the host.
  - Generation for VSE Feature Reference
    This reference manual provides z/VSE-specific information about developing and generating EGL programs in the VSE environment.
- Source code analysis with code review
  With code review, you can create configurations of coding rules for EGL source code. You can then run the configurations to check the source code for consistency with the rules.
- Responsive Design Support in IBD
  What is Responsive Design? Responsive design is an approach for creation of web pages that automatically scales its content and elements to match the screen size on which it is viewed. So, instead of designing multiple websites for different devices with variable screen sizes, we can design just one website that scales up or down automatically, to match the device it’s being viewed on.
- Containerizing an EGL RUI Application
Samples
Troubleshooting and support
EGL runtime error messages
Reference
Glossary
Using the help
Notices for IBM Business Developer documentation

SQL record internals

You need to be aware of the internal layout of an SQL record in any of these situations:

You use an EGL assignment statement to copy an SQL record to or from a record of a different type
The runtime argument passed to an EGL program is an SQL record, but the program parameter is not an SQL record
The runtime argument passed to an EGL function is an SQL record
You receive an SQL record as a parameter in a non-EGL program
You use an SQL record as the original or redefining record in a record redefinition.

Four bytes precede the business data in each structure field in an SQL record. The first two bytes are a null indicator, and a null is interpreted as any negative value. The second two bytes are reserved for use as a length field, and you should not access that field.