Apress.Expert.Oracle.Database.Architecture.9i.and.10g.Programming.Techniques.and.Solutions.Sep.2005

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CHAPTER 15 ■ DATA LOADING AND UNLOADING
Use the STR Attribute
This is perhaps the most flexible method of loading data with embedded newlines. Using the
STR attribute, we can specify a new end-of-line character (or sequence of characters). This
allows us to create an input data file that has some special character at the end of each line—
the newline is no longer “special.”
I prefer to use a sequence of characters, typically some special marker, and then a newline.
This makes it easy to see the end-of-line character when viewing the input data in a text
editor or some utility, as each record still has a newline at the end of it. The STR attribute is
specified in hexadecimal, and perhaps the easiest way to get the exact hexadecimal string we
need is to use SQL and UTL_RAW to produce the hexadecimal string for us. For example, assuming
we are on UNIX where the end-of-line marker is CHR(10) (linefeed) and our special marker
character is a pipe symbol (|), we can write this:
ops$tkyte@ORA10G> select utl_raw.cast_to_raw( '|'||chr(10) ) from dual;
UTL_RAW.CAST_TO_RAW('|'||CHR(10))
-------------------------------------------------------------------------------
7C0A
which shows us that the STR we need to use on UNIX is X'7C0A'.
■Note On Windows, you would use UTL_RAW.CAST_TO_RAW( '|'||chr(13)||chr(10) ).
To use this, we might have a control file like this:
LOAD DATA
INFILE demo.dat "str X'7C0A'"
INTO TABLE DEPT
REPLACE
FIELDS TERMINATED BY ','
TRAILING NULLCOLS
(DEPTNO,
DNAME "upper(:dname)",
LOC
"upper(:loc)",
COMMENTS
)
So, if our input data looks like this:
[tkyte@desktop tkyte]$ cat demo.dat
10,Sales,Virginia,This is the Sales
Office in Virginia|
20,Accounting,Virginia,This is the Accounting
Office in Virginia|
30,Consulting,Virginia,This is the Consulting