Reputation: 3233
What is Oracle SQL Loader?
What is Oracle SQL Loader and what is it used for?
Upvotes: 0
Views: 622
Answers (3)
Reputation: 35
To transfer data from one Oracle database to another oracle database, we use oracle data pump. And in oracle versions previous to 10g we use oracle export/import. But if you want to transfer data from a non oracle database to an oracle database, you create a flat file of the data in the non oracle database and using SQL Loader load the data into oracle database.
Following is procedure to load the data from Third Party Database into Oracle using SQL Loader.
1.Convert the Data into Flat file using third party database command.
2.Create the Table Structure in Oracle Database using appropriate datatypes
3.Write a Control File, describing how to interpret the flat file and options to load the data.
4.Execute SQL Loader utility specifying the control file in the command line argument
Upvotes: 0
Reputation: 146329
SQL Loader is utility provided by Oracle which enables us to load data from flat files into database tables. It is well covered in the documentation (check the Utilities Guide). The key thing is that SQL Loader is an external OS program.
External tables were introduced in Oracle 9i, allowing us to define tables whose data is supplied from flat files. These provide most of the functionality of SQL Loader with a lot more convenience. For instance we can manipulate and re-format the data using SQL functions which is simpler than using SQL Loader's syntax. It also means that we can pull the data from inside the database rather than pushing it from the OS.
However, for loading huge volumes of data in ultra-quick time a well-tuned SQL Loader control file will beat external tables for performance. Also, if there is a complicated OS process associated with the data files - e.g. ftp, gunzip, pre-processing with sed or awk - it can be more convenient to call SQL Loader from inside the shell script rather than attempting to hook up with a database job. So SQL Loader is still useful in certain scenarios but it is not necessarily the automatic first choice.
Upvotes: 5
