OpenEdge

Question 0

What does set do?

Answer 0

It requests input, then put the data into the screen buffer frame and into the specified fields and variables.

Question 1

What does Update do?

Answer 1

Displays the specified fields, prompts for input, puts the input data into the screen buffer and the specified fields and variables as well.

Question 2

What does assign do?

Answer 2

It moves data from the screen buffer to the record buffer.

Question 3

What does Commit do?

Answer 3

During a transaction, progress writes data to one or more databases as prog control passes through DB update statements. Progress uses a two stage commit to commit changes to DB. First it checks to see if all databases are reachable. Then it does its validation checks. If any one thing fails to check out in either check, progress backs out the transaction and returns the DB to its pre transaction state using the before-image files. If everything checks out, progress commits the changes to the databases.

Question 4

What is a before image file?

Answer 4

During a transaction, information on all database activity occurring during that transaction is written to a before image file. Progress maintains one for each database. The information written is carefully coordinated with the timing of the data written to the actual database table. That way if an error occurs during the transaction, progress uses this before image file to restore the DB to the condition it was in before the transaction started.