October 1996
Intermediate to advanced
687 pages
16h 41m
English
Content preview from Advanced Oracle PL/SQL Programming with Packages
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
13.1. A Review of UTL_FILE
Before you dive in to using either UTL_FILE or the PLVfile package, however, you should review the following information about UTL_FILE. Chapter 15 of Oracle PL/SQL Programming offers more detail about these topics and the programs of the UTL_FILE package. The following sections offer some information about UTL_FILE that you need to know in order to use PLVfile properly.
13.1.1. Enabling File Access in the Oracle Server
To use the UTL_FILE package, you must add a line to the initialization file or init.ora for your database instance that indicates the directories in which you can read and write operating system files. This precaution is taken by Oracle so that you do not inadvertently corrupt important files like the database log files.
The entry in the init.ora file can have one of two formats:
utl_file_dir='*'
or
utl_file_dir='dir1,dir2...dirn'
where dir1 through dirn are individual, specific directory listings. If you use the first format, you are telling the Oracle database that developers can use UTL_FILE to write to any directory.
13.1.2. File Handles
Before you can do anything with a file, you have to open it (this process is explained below). At this point, UTL_FILE returns a handle or pointer to that file. You will then use this handle in all future manipulations of the file. A file handle has a special datatype of UTL_FILE.FILE_TYPE. FILE_TYPE is actually a PL/SQL record whose fields contain all the information about the file needed ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.