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5.	What is checkpoint?
	A checkpoint is a point when a background process updates the headers of all datafiles and control files to synchronize the files. At checkpoint, DataBase Writer (DBWR) writes the dirty buffers to the datafile.
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6.	What is a locally managed tablespace?
	A locally managed tablespace keeps track of its own block and maintains the information in a bitmap in the header section rather than in the data dictionary. Each bit in the bitmap corresponds to a block or a group of blocks. When the extends are allocated or freed for reuse, Oracle changes the bitmap values to show the new status of the blocks. These changes do not generate rollback information because they do not update tables in the data dictionary, unlike the default method of Dictionary – Managed Tablespace.
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7.	How would you force a log switch?
	A log switch can be forced by using the ALTER SYSTEM SWITCH LOGFILE; statement.
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8.	What is row chaining?
	Row chaining is a situation when a single row is stored in multiple blocks. It happens when row is too big to fit into a single block. In other words, row chaining occurs when row size is greater than blocksize. Tables with the LONG and LONG RAW columns are more likely to have chained rows. In addition tables with more than 255 columns will have chained rows.
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