Structured Query Language (SQL) is a universal language to access the relational database. It belongs to the fourth-generation language (4GL). Its execution characteristics are non-process, that is, the specific methods and ways do not indicate the implementation. Instead, simply call the corresponding statement to achieve the results directly. Obviously, this language that does not pay attention to any detail has great convenience for developers.
However, for some complex business processes, the corresponding procedures are required to describe, then 4GL is a bit of powerful. The emergence of PL / SQL is to solve this problem, and PL / SQL is a procedural language, which is the third generation language. It focuses on processing details as languages such as C, C , Java, so it can be used to implement comparison Complex business logic.
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Oracle PL / SQL Getting Started
