Database Terms

To understand how VB supports database use, you must first understand terms related to database technology.

• SQL : SQL stands for structured quesry language. It is a language that enables you to perform operations such as retrieveing data, sorting data, adding new data, deleting data, or updating data in relational databases.
• Tables : Tables are storage areas for specific types of information. For example, customer data table, a vendor data table, employee data table, etc. A table is made up of columns, which describe each attribute of an item stored in the table, and of rows, which are individual records in the database. Columns have names, data types, and sizes. A single record in a table is made up of one row containing all of the columns in the table.
• Primary Key : Primary key uniquely identifies a single row in a table.
• Foreign Key : It refers to a column in a secondary table that is related to column in a primary table.
• Index : An index is built on table columns and is used to speed up the retrieval of data from an executing query. Indexes are used to sort the data in specific ways.
• Queries : A query is an SQL statement used to retrieve rows of information from one or more tables.