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ORACLE8i- P26: We want information information.” Possibly you recognize these words as the primary interest of a somewhat clandestine group, and as told by a character called Number 2 to Patrick McGoohan’s character Number 6 (in the old TV show The Prisoner). Indeed, in this day, information is king, and the speedy, accurate, and reliable retrieval of this information is paramount. | LOADING OBJECTS COLLECTIONS AND LOBS 999 employees COLUMN OBJECT emp_name CHAR 30 emp_age INTEGER EXTERNAL 3 emp_id CHAR 7 NULLIF emps.emps.emp_id BLANKS projects NESTED TABLE SDF CONSTANT pr.txt fix 71 project_id char 5 INTEGER EXTERNAL 5 project_name char 30 CHAR NULLIF projects.project_name BLANKS proj_desc LOBFILE proj_desc.txt CHAR 2000 TERMINATED BY n In this example we have a VARRAY of employees and a nested table of projects. If the filler column EMP_CNT is 0 then the array is initialized to EMPTY and if the COUNT is greater then 0 then the VARRAY is created with the number of elements equal to EMP_CNT. As for the nested table of projects we just load the data into the nested table since it has no limitations on rows as does the VARRAY. LOBs Following are the four types of LOBs Large Objects supported by SQL Loader processing BLOB is a Binary Large Object that can store up to 4GB of data. This type actually stores its data in the table. CLOB is a Character Large Object that can store up to 4GB of data. This type actually stores its data in the table. NCLOB is a national character set of CLOB. This type actually stores its data in the table. BFILE means Binary Large Object. This type is only a pointer to an external file supported and maintained by the operating system. Unlike the other three LOB types the BFILE has no size limit imposed by Oracle but is limited by the operating system. Listing 22.14 has two examples of loading LOBs in SQL Loader. In the first the LOBs are loaded from a delimited field the second example loads LOBs from LOB files. NOTE During the load process SQL Loader reads the LOB file in 64KB chunks and stores the data like any other record type. In order for Oracle to load physical records larger than 64KB you must use the READSIZE command-line parameter to specify a larger record size. Beyond Simple Database Managment Please purchase PDF Split-MJe 9e n wwwi.wypdfecom to removebihis watermark. 1000 CHAPTER 22 SQL LOADER Listing 22.14 .
