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Oracle Built−in Packages- P83

Oracle Built−in Packages- P83: Ah, for the good old days of Version 1.0 of PL /SQL! Life was so simple then. No stored procedures or functions and certainly no packages. You had your set of built−in functions, like SUBSTR and TO_DATE. You had the IF statement and various kinds of loops. With these tools at hand, you built your batch−processing scripts for execution in SQL*Plus, and you coded your triggers in SQL*Forms 3.0, and you went home at night content with a good day's work done. | Appendix A What s on the Companion Disk BEGIN INSERT INTO my_book_text chapter_descr chapter_text VALUES Table of Contents EMPTY_CLOB RETURNING chapter_text INTO chapter_loc chapter_length DBMS_LOB.GETLENGTH chapter_loc DBMS_OUTPUT.PUT_LINE Length of Table of Contents chapter_length EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.PUT_LINE OTHERS Exception sqlerrm END This is the output of the script Length of Table of Contents 0 Note that EMPTY_CLOB can be used to populate both CLOB and NCLOB columns. EMPTY_BLOB and EMPTY_CLOB can be called with or without empty parentheses. NOTE Do not populate BLOB CLOB or NCLOB columns with NULL values. Instead use the EMPTY_BLOB or EMPTY_CLOB functions which will populate the columns with a valid LOB locator and set the associated data to NULL. PREVIOUS HOME NEXT 8.1 Getting Started with B00KIHDEX 8.3 DBMS_LOB Interface DBMS_LOB . Orocle PL SQL Oracle PL SQL Oracle Advanced PL SQL Oracle Wei Applications Oracle PL SQL Oracle PL SQL Programming. I Programming I Budt-in I Programming I PL SQL Developer s I Language I Bait-ins MM Second Edition Guide to Orndo8i Features Packages wrtk Packages Introduction Pocket Reference Pocket Reference Copyright c 2000 O Reilly Associates. All rights reserved. 8.2.3 Internal LOB Considerations 401 Oracle Built-in Packages SEARCH Chapter 8 Managing Large Objects NEXT 8.3 DBMS_LOB Interface This section describes the programs available through the DBMS_LOB packages in several categories. 8.3.1 Working with BFILEs The following sections describe the programs in the DBMS_LOB package that perform operations on BFILE objects. 8.3.1.1 The DBMS_LOB.FILEEXISTS function The FILEEXISTS function indicates whether the given BFILE locator points to a file that exists in the operating system. Here s the specification for this program FUNCTION DBMS_LOB.FILEEXISTS file_loc IN BFILE RETURN INTEGER The file_loc parameter is the name of the file locator. The function returns one of the following values Value Description 0