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Oracle SQL Plus The Definitive Guide- P46

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Oracle SQL Plus The Definitive Guide- P46:Every day, computer professionals the world over wake up, travel to the office, sit down in front of a computer, and begin another day working with that database called Oracle. Programmers write queries and stored procedures. Database administrators monitor performance, make database changes, and perform other maintenance tasks. Operations people may need to back up or recover a database.v | previous page page_413 next page Page 413 SET SCAN OFF ON SET SCAN Is the command which may not be abbreviated. OFF Disables variable substitution and has the same effect as SET DEFINE OFF. ON Enables variable substitution and has the same effect as SET DEFINE ON. The SET SCAN command duplicates functionality provided by the SET DEFINE command. Large Object Settings Large object settings control the way SQL Plus handles columns with a datatype of LONG. The most commonly adjusted setting is the LONG setting which controls the maximum number of characters SQL Plus will display from a LONG. The complete list of LONG settings is shown here LOBOFFSET An index into the LONG column specifying the first character to be displayed. LONG Specifies the maximum number of characters to display from a LONG column. LONGCHUNKSIZE Controls the number of characters retrieved from a LONG at one time. Chapter 7 Advanced Scripting contains examples showing how to use these three settings. SETLOBOFFSET The LOBOFFSET setting represents an index into a LONG column. When SQL Plus displays a LONG it begins with the character pointed to by LOBOFFSET. SET LOBOF FSET offset where SET LOBOF FSET Is the command which may be abbreviated to SET LOBOF. ffset Is the offset used when retrieving LONG values and represents the first character you want to display. Using the LOBOFFSET setting in conjunction with the LONG setting allows you to print any arbitrary substring from a LONG column. previous page page_413 next page previous page page_414 next page Page 414 SETLONG The LONG setting controls the number of characters displayed by SQL Plus from any LONG columns returned by a query SET LONG long_length where SETLONG Is the command which may not be abbreviated. longlength Represents the number of characters you want displayed from any LONG columns you select from the database. The default setting is to display 80 characters. SET LONGCHUNKSIZE The LONGCHUNKSIZE is a performance-related setting. It .