release statement

Review the following information regarding the release statement:

• You can use the release statement to release a lock, even if it is under a transaction.
• If file.var and ID.exp are both omitted, all items currently locked by the current process are unlocked.
• If ID.exp is specified without file.var, the default file variable is used.

In the following example, an item is read from the customer file and locked.

• If a new name is entered, the name attribute is changed, a date stamp is placed in attribute 20, and the item is written, automatically clearing the item lock.
• If no name is entered, no write occurs, requiring the item lock to be cleared with the release statement.

 readu item from customer.file,item-ID then
    input name
    if name # ’’ then
       item<1>=name
       item<20>=date()
       write item on customer.file,item-ID
    end else
       release customer.file,item-ID
    end
 end

 begin work
 for i = 1 to 100
    write i:space(100) on i 
 next i
 for i = 1 to 100
    if mod(i,2) = 0 then
      readu xx from i
    end else
      read xx from i
    end
    if xx # i:space(100) then msg= "2 - failed read ":i; goto fail
 next i
 for i = 1 to 100 step 3
   release i
 next i

 crt "Now check the locks, then hit return to continue"; in i
 rollback work;* do a rollback instead

Results:

 :list-locks (i

 Item Locks          PIB#  Lvl  Hash  Item-id              Filename
  1623204 (0018C4A4)    1   1 00000032  2                    %1806329804.16720a
  1623205 (0018C4A5)    1   1 00000033  3                    %1806329804.16720a
  1623207 (0018C4A7)    1   1 00000035  5                    %1806329804.16720a
  1623208 (0018C4A8)    1   1 00000036  6                    %1806329804.16720a
  1623210 (0018C4AA)    1   1 00000038  8                    %1806329804.16720a
  1623211 (0018C4AB)    1   1 00000039  9                    %1806329804.16720a
  1623212 (0018C4AC)    1   1 0000021B  11                   %1806329804.16720a
  1623213 (0018C4AD)    1   1 0000021C  12                   %1806329804.16720a