Tables and flat files have rows and columns of information., Scalability means a system can grow when demand does., Data persistence means data might be stored forever., A relational database links the information in different tables., A null value means there is no data., A logical schema outlines the structure of a database., Physical schema refers to the actual tables, columns and relationships created in the RDBMS., A row in a table is called a record., A column in a table is called a field., A primary key identifies a record uniquely., Constraints set limitations to prevent problems with a database., Queries are questions a database can answer., Non-structured data like pictures and documents don't fit into a database., Metadata is an example of semi-structured data., Two types of databases are document and key/value., Different types of access are manual, direct, programmatic, user interface and utility., Global or server permissions are usually only for an administrator account., Permissions can be granted, denied or revoked., The drop command deletes database objects., A database dump is a one-time backup of a database that exports the schema, tables, views with the data.

Understanding Databases (7.1)

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