LINE_EXISTS( ) - To check if a particular entry with specified key is present in the internal table or not!

• The predicate function line_exists can be considered as a short form of the statement READ TABLE with the additionTRANSPORTING NO FIELDS following by sy-subrc being checked.
• The predicate function line_exists cannot be used to determine the row number in a table index of a search key, since table expressions do not fill the system field sy-tabix. 

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