Diff between delete and refresh

Question

urgent

Answer 1

refresh : It will delete the records but memory will be there.
delete : delete the required records.
Syntax
REFRESH itab.
Effect
This statement sets an internal table itab to its initial value, meaning that it deletes all rows of the internal table. The memory space required for the table is freed up to the initial memory size INITIAL SIZE. For itab, you must specify an internal table.
To delete all rows and free the entire memory space occupied by rows, you can use the statement FREE.
Note
The statement REFRESH itab acts for all internal tables like CLEAR itab[]. If an internal table itab has a header line, then the table body and not the header line is initialized. If the internal table itab has no header line, REFRESH itab acts like CLEAR itab. Therefore, you should always use CLEAR instead of REFRESH.
Exceptions
Non-Catchable Exceptions
Cause: No more memory space available to create the table
Runtime Error: REFRESH_NO_SHORT_MEMORY
DELETE
delete <itab> where <condition>
DELETE for Files
Deletes files on the application server
Syntax
DELETE DATASET <dsn>.
Deletes the file <dsn> from the file system of the application server.
DELETE for Database Table Entries
Deletes entries from database tables.
Syntax
DELETE FROM <dbtab> WHERE <cond>.
All of the lines in the database table that satisfy the conditions in the WHERE clause are deleted.
Syntax
DELETE <dbtab> FROM <wa>.
DELETE <dbtab> FROM TABLE <itab>.
This deletes the line that has the same primary key as the work area <wa>, or deletes all the lines in the database that have the same primary key as a line in the internal table <itab>. The work area <wa> or the lines of the internal table <itab> must have at least the same length as the work area of the database table.
DELETE for Cluster Databases
Deletes data clusters from cluster database tables.
Syntax
DELETE FROM DATABASE <dbtab>(<ar>) ID <key>.
Deletes the entire cluster in area <ar> with the name <key> from the cluster database table <dbtab>.
DELETE for the Cross-Transaction Application Buffer
Deletes data clusters from the cross-transaction application buffer.
Syntax
DELETE FROM SHARED BUFFER <dbtab>(<ar>) ID <key>.
Deletes the data cluster for the area <ar> with the name <key> stored in the cross-transaction application buffer for the table <dbtab>.
DELETE for Lines from an Internal Table
Deletes lines from internal tables of any type.
Syntax
DELETE TABLE <itab> FROM <wa>.
DELETE TABLE <itab> WITH TABLE KEY <k1> = <f 1>... <k n> = <f n>.
Deletes using the table key. All lines with the same key are deleted. The key values are taken either from a compatible work area <wa> or specified explicitly.
Syntax
DELETE <itab> WHERE <cond>.
Deletes using conditions. Deletes all table entries that satisfy the logical expression <cond>. The logical condition can consist of more than one comparison. In each comparison, the first operand must be a component of the line structure.
Syntax
DELETE ADJACENT DUPLICATE ENTRIES FROM <itab> http://COMPARING... .
Deletes adjacent duplicate entries, either by comparing the key fields or the comparison fields specified explicitly in the COMPARING addition.
DELETE for Lines from Index Tables
Deletes entries from index tables.
Syntax
DELETE <itab> INDEX <idx>.
If you use the INDEX addition, the line with index <idx> is deleted from the table <itab>. Without the INDEX addition, you can only use the above statement within a LOOP. In this case, you delete the current line.
Syntax
DELETE <itab> FROM <n1> TO <n 2> WHERE <cond>.
The system deletes all of the lines of <itab> whose index lies between <n 1 > and <n 2 > and who meet the conditions specified in the WHERE clause. If you do not specify a FROM addition, the system deletes lines from the first line onwards. If you do not specify a TO addition, the system deletes lines up to the last line. The logical condition can consist of more than one comparison. In each comparison, the first operand must be a component of the line structure.
REFRESH
Initializes an internal table.
Syntax
REFRESH <itab>.
Resets the internal table <itab> to its initial value, that is, deletes all of its lines.
REFRESH CONTROL
Initializes a control.
Syntax
REFRESH CONTROL <ctrl> FROM SCREEN <scr>.
The control <ctrl> defined in the CONTROLS statement is reset with the initial values specified for screen <scr>.
hope it will be useful.
Reward points Please..