Oracle interview questions-Technical Article (1)

This may be what you have been expectingArticle, While paying attention to this part of technical questions, please be sure to read the questions and answers related to the individual during the interview. The answer here is not comprehensive. These questions can be explained from multiple perspectives. Maybe you don't have to give a full answer during the interview, you only need to answer your questions to familiarize the interview examiner with Oracle concepts.

1. Explain the differences between cold backup and hot backup and their respective advantages

Answer: Hot Backup is applicable to databases in the archive mode. When the database is still in the working state, it is backed up. Cold backup refers to the backup after the database is closed, applicable to all databases. The advantage of hot backup is that the database can still be used during Backup and can be restored to any point in time. The advantage of cold backup is that its backup and recovery operations are quite simple, and because cold backup databases can work in non-archive mode, the database performance will be slightly better than the archive mode. (Because archive log is not necessarily written to the hard disk)

2. You must use backup to restore the database, but you do not have control files. How can this problem be solved?

A: recreate the control file and use the recover command with the backup control file clause to restore the database.

3. How to convert init. ora to spfile?

A: Use the create spfile from pfile command.

4. Explain the differences between data block, extent, and segment (the term here is recommended)

A: data block is the smallest logical storage unit in the database. When database objects require more physical storage space, continuous data blocks constitute extent. All extents owned by a database object are called the segment of this object.

5. Two Methods of checking table structure are provided.

Answer: 1. Describe command

2. dbms_metadata.get_ddl package

6. How to view database engine errors

Answer: Alert Log.

Author: black_snail Il