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The SQL and SQL*Plus module of the Introduction to Oracle course covered relational database concepts, the SQL command language, and SQL*Plus commands to execute and format SQL commands. | 17 Summary of SQL and SQL Plus ORACLG 17-2 Introduction to Oracle SQL and PL SQL Using Procedure Builder Summary of SQL and SQL Plus The SQL and SQL Plus module of the Introduction to Oracle course covered relational database concepts the SQL command language and SQL Plus commands to execute and format SQL commands. Database Terminology Concept Description Table A table is the basic storage structure of an RDBMS consisting of one or more columns and zero or more rows. Row A row is a combination of column values in a table for example the information about one department in the table S_DEPT. A row is sometimes called a record. Column A column represents one kind of data in a table for example the department name in the example table S_DEPT. It is described with a column name and holds data of a specific type and size. Field At the intersection of a row and a column you find a field. The field can contain data. If there is no data in the field it is said to contain a null value. Primary key A primary key is the column or set of columns that uniquely identifies each row in a table for example a department number. It must contain a value. Foreign key A foreign key is a column or set of columns that refers to a primary key in the same table or in another table. You create them to enforce relational database design rules. Summary of SQL and SQL Plus .
