Oracle Database 10g Foundation Learning (i)

Oracle starts from scratch and is overwhelmed. The best way to master a skill is to learn how to use it, then learn it in depth, first look, then technology.

One, what is a database? Why do I need a database?

A database is essentially a list of information, or a set of work-together lists that a database program can be considered as a list manager. Simple information can be recorded in a spreadsheet, and then the intricate list of information needs to be managed by the database, the database has a variety of performance: more rows, allowing many users to use simultaneously, security, relationship ability, to ensure data quality constraints.

Second, the role and characteristics of SQL?

Structure Query Language (SQL) is a structured query language, which is the most popular data query and UPDATE statement in relational database management system.

Third, the relationship between SQL and SQL *plus?

SQL *plus is a powerful tool for connecting to an Oracle database that users use to connect to the database and perform operations. SQL *plus is two different languages, SQL is an interface for user-written SQL and PL/C scripts , and SQL *plus can pass user input to the Oracle database for processing and return the response results to SQL *plus. The results are then returned to the database user.

Four, SQL sentence learning

Http://www.cnblogs.com/sunada2005/p/3411873.html

Note: The use of Oracle's NVL () function: Nvl (ARG, value) means that if the value of the preceding ARG is null then the returned value is the following , not NULL, to return ARG, such as: NVL (A, A, b) is to determine whether a is Null if the value of A is not returned if it is a value that returns B .

Five, the basis of PL/SQL

Learning Links: http://www.cnblogs.com/fanyong/archive/2013/02/25/2932673.html

Oracle Database 10g Foundation Learning (i)