Difference Between SQL and PL/SQL
SQL, Structured Query Language, is a standard database language used to create, maintain and retrieve relational databases, and PL/SQL, the procedural language of SQL Extensions, which extend SQL and provide procedural capabilities.
The following are the important differences between SQL and PL/SQL.
Serial number | Keywords | SQL | PL/SQL |
---|---|---|---|
1 | Definition | SQL is a structured query language for databases. | PL/SQL is a programming language that uses SQL. |
2 | Variables | SQL has no variables. | PL/SQL has variables, data types, etc. |
3 | Control structure | SQL does not have FOR loops, if controls, and similar structures. | PL/SQL has FOR loops, while loops, if controls and other similar structures. |
4 | Operation | SQL can only perform one operation at a time. | PL/SQL can perform multiple operations at the same time. |
5 | Language type | SQL is a declarative language. | PL/SQL is a procedural language. |
6 | Embedding | SQL can be embedded in PL/SQL blocks. | PL/SQL can also be embedded in SQL code. |
6 | Interaction | SQL interacts directly with the database server. | PL/SQL does not interact directly with the database server. |
7 | Positioning | SQL is a data-oriented language. | PL/SQL is an application-oriented language. |
8 | Objective | SQL is used to write queries, create and execute DDL and DML statements. | PL/SQL is used to write program blocks, functions, procedures, triggers and packages. |
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