EGL statements

The topic outlines the EGL statements used for general purposes and then the EGL statements used for data access.
Table 1. EGL statements used for general purposes
Statement Type Purpose
assignment Assigns the value of an expression to a data area
call Calls a service from a Rich UI application, or calls a program from a service
case Runs one of several alternative sets of statements
comment Documents code
declaration Declares variables and constants
function invocation Calls a function
continue Returns control to the start of an enclosing loop in the same function
exit Ends the processing of the nearest enclosing statement of a stated kind
for Defines a block of statements that run in a loop until a specified value is reached
for  
if, else Defines a block of statements that run if and only if a specified condition applies; also defines an alternative block
move Copies data from a source to a target, with processing that is not available in an assignment statement
return Returns control from a function, and optionally, returns a value to the invoker
set To establish characteristics of a field or record; for example, to reset the field values to those initially specified in the Record part definition
try, throw To include exception handling in your logic
while Defines a block of statement that run in a loop until a test fails

The next table outlines the EGL statements for data access. In your product, these statements are available only when you are writing services or libraries invoked from services.

Table 2. EGL statements used for data access
Statement Type Purpose
add Places a record in a file, message queue, or database; or, places a set of records in a database
close Closes the file or message queue that is associated with a given record; disconnects from a printer; or, in the case of an SQL record, closes the cursor, which is a set of database rows, that was made available by an EGL open or get statement
delete Removes a record from a file or a row from a relational database
execute Runs one or more SQL statements; in particular, SQL data-definition statements, such as CREATE TABLE, and data-manipulation statements, such as INSERT or UPDATE
forEach Processes data from each of several relational-database rows that are returned from an open or get statement
get Retrieves a single file record or database row (or retrieves a set of database rows), so that the retrieval can allow for a subsequent use of the update or delete statement
open Selects a set of rows from a relational database
prepare Specifies an SQL PREPARE statement, which builds a database-access statement at run time
replace Places a changed record into a file or database

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