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

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CHAPTER 15 ■ DATA LOADING AND UNLOADING
How Do I Load Delimited Data?
Delimited data, or data that is separated by some special character and perhaps enclosed in
quotes, is the most popular data format for flat files today. On a mainframe, a fixed-length,
fixed-format file would probably be the most recognized file format, but on UNIX and NT,
delimited files are the norm. In this section, we will investigate the popular options used to
load delimited data.
The most popular format for delimited data is the comma-separated values (CSV) format.
In this file format, each field of data is separated from the next by a comma. Text strings can
be enclosed within quotes, thus allowing for the string itself to contain commas. If the string
must contain a quotation mark as well, the convention is to double up the quotation mark (in
the following code we use "" in place of just "). A typical control file to load delimited data will
look much like our first example earlier, but the FIELDS TERMINATED BY clause would generally
be specified like this:
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
It specifies that a comma separates the data fields, and that each field might be enclosed
in double quotes. If we were to modify the bottom of this control file to be
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
(DEPTNO, DNAME, LOC )
BEGINDATA
10,Sales,"Virginia,USA"
20,Accounting,"Va, ""USA"""
30,Consulting,Virginia
40,Finance,Virginia
when we run SQLLDR using this control file, the results will be as follows:
ops$tkyte@ORA10G> select * from dept;
DEPTNO DNAME
LOC
---------- -------------- -------------
10 Sales Virginia,USA
20 Accounting Va, "USA"
30 Consulting Virginia
40 Finance Virginia
Notice the following in particular:
• Virginia,USA in department 10: This results from input data that was "Virginia,USA".
This input data field had to be enclosed in quotes to retain the comma as part of the
data. Otherwise, the comma would have been treated as the end-of-field marker, and
Virginia would have been loaded without the USA text.
• Va, "USA": This resulted from input data that was "Va, ""USA""". SQLLDR counted
the double occurrence of " as a single occurrence within the enclosed string. To load a
string that contains the optional enclosure character, you must ensure the enclosure
character is doubled up.