VisualAge Generator to Enterprise Generation Language Migration Guide
VisualAge Generator: The length for pack data items is
specified as the number of digits, up to a maximum of 18. Even lengths
are recorded within the shared data item definitions and for nonshared data
items within record definitions. However, in most editors, and in test
and generation, the length that is used is the next higher odd length, with a
maximum of 18. Only the SQL Record Editor displays the even
length. For even length items used as host variables in SQL WHERE
clauses or in SQL statements that specify Execution Time Statement Build, test
and generation create a temporary variable with the even length.
EGL: In VisualAge Generator Compatibility mode, EGL test
and generation provide the same support as in VisualAge Generator. For
decimal items with even precision, test and generation increase the precision
by one in all records and use a temporary variable with the even precision in
SQL where clauses or prepare statements. If VisualAge Generator
Compatibility mode is not specified, EGL uses the precision specified for the
data item.
Associated part needed for migration: Not
applicable.
Figure 9. Pack data items with even length
Migrating with the associated part
| Migrating without the associated part
|
The migration tool migrates pack data items with even lengths as
follows:
- Uses the even or odd length specified in VisualAge Generator for shared
data item definitions, regardless of whether the item is ever used in an SQL
row record.
- Uses the even or odd length specified in VisualAge Generator for nonshared
items in all record definitions, because the item might be used as a host
variable in an SQL where clause or prepare statement.
- Uses an odd length (or 18 if the item is the maximum length) for nonshared
items in tables, function parameters, function return values, and function
local storage because the information to determine an even number of digits
was not recorded in VisualAge Generator in these situations.
|
The migration tool does the same things as mentioned in the Migrating
with the associated part column.
|
Potential Problem: A problem only arises if you eliminate
the use of VisualAge Generator Compatibility mode. In this situation,
overflow might occur due to having fewer significant digits than in VisualAge
Generator Compatibility mode.
Potential Solution: Before eliminating VisualAge Generator
Compatibility mode, do the following:
- Review your SQL table and view definitions to determine if you have any
SQL columns that require even precision. If so, assess the SQL
performance impact of using host variable lengths that do not match the SQL
column definition.
- Review all decimal data item definitions and primitive data item
definitions in EGL records for even length items. Assess whether
overflow might occur for any of these items.
|
Potential Problem: The same potential problem and
solution as listed in the Migrating with the associated part column
apply.
|
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