SQLLoader

SQLLoader is a data loading utility provided by Oracle Corporation for loading data from external files into Oracle databases. It is a command-line tool that reads data from various file formats such as fixed-length, variable-length, and delimited files, and inserts it into Oracle tables. SQLLoader is particularly useful for bulk data loading operations, which can significantly improve performance compared to individual insert statements.

The tool operates by using a control file, which specifies the structure of the input data file, the target table in the database, and other parameters such as field delimiters and data transformations. The control file is written in a simple, declarative language that is easy to understand and modify. SQLLoader supports a wide range of data types and can handle complex data structures, including nested tables and object types.

One of the key features of SQLLoader is its ability to perform direct-path loading, which bypasses the buffer cache and writes data directly to the data files on disk. This method can significantly reduce the time required to load large volumes of data. SQLLoader also supports parallel data loading, allowing multiple processes to load data concurrently, further enhancing performance.

In addition to its primary function of data loading, SQLLoader can also be used for data transformation and validation. It provides various options for data manipulation, such as concatenating fields, converting data types, and applying conditional logic. SQLLoader can also generate log files that record the results of the data loading process, including any errors or warnings encountered.

Overall, SQLLoader is a powerful and flexible tool for loading data into Oracle databases. Its ability to handle large volumes of data efficiently, combined with its support for data transformation and validation, makes it an essential component of many Oracle database management strategies.