tailieunhanh - Loading Data into a Database - 19

Data Loading Methods Several methods are available for loading data into tables in an Oracle database. Of the methods available, Direct Load insert and SQL*Loader are discussed here. Export and Import are covered in the Oracle9i Database Administration Fundamentals II course. SQL*Loader SQL*Loader loads data from external files into tables of an Oracle database. It has a powerful data parsing engine that places little limitation on the format of the data in the data file. Direct Load Direct Load insert can be used to copy data from one table to another table within the same database. It speeds up the insert operation, bypassing the. | Loading Data into a Database Objectives After completing this lesson, you should be able to do the following: Demonstrate usage of Direct Load operations Describe the usage of SQL*Loader Perform basic SQL*Loader operations List guidelines for using SQL*Loader and Direct Load Data Loading Methods Oracle database SQL*Loader Other applications Export Import Direct Load Oracle database Data Loading Methods Several methods are available for loading data into tables in an Oracle database. Of the methods available, Direct Load insert and SQL*Loader are discussed here. Export and Import are covered in the Oracle9i Database Administration Fundamentals II course. SQL*Loader SQL*Loader loads data from external files into tables of an Oracle database. It has a powerful data parsing engine that places little limitation on the format of the data in the data file. Direct Load Direct Load insert can be used to copy data from one table to another table within the same database. It speeds up the insert | Loading Data into a Database Objectives After completing this lesson, you should be able to do the following: Demonstrate usage of Direct Load operations Describe the usage of SQL*Loader Perform basic SQL*Loader operations List guidelines for using SQL*Loader and Direct Load Data Loading Methods Oracle database SQL*Loader Other applications Export Import Direct Load Oracle database Data Loading Methods Several methods are available for loading data into tables in an Oracle database. Of the methods available, Direct Load insert and SQL*Loader are discussed here. Export and Import are covered in the Oracle9i Database Administration Fundamentals II course. SQL*Loader SQL*Loader loads data from external files into tables of an Oracle database. It has a powerful data parsing engine that places little limitation on the format of the data in the data file. Direct Load Direct Load insert can be used to copy data from one table to another table within the same database. It speeds up the insert operation, bypassing the database buffer cache and writing data directly into the data files. Direct Load Direct Load insert can be performed in the following ways: Normal (serially), or in parallel Into partitioned tables, nonpartitioned tables, or single partitions of a table With or without logging of redo data Direct Load Direct Load insert (serial or parallel) can only support the INSERT . SELECT syntax of an INSERT statement, not the INSERT . Values syntax. The parallelism for INSERT . SELECT is determined from either parallel hints or parallel table definition. Oracle9i provides syntax extensions that extend the scope of the INSERT . SELECT statement, so that you can insert rows into multiple tables as part of a single DML statement. A Direct Load insert can be invoked by using the APPEND hint, as shown in following command: INSERT /*+APPEND */ INTO [ schema. ] table [ [NO]LOGGING ] sub-query; where: schema: Is the owner of the table table: Is the name of the table .