SQL

Table of Contents

SQL

SQL Queries

Running example

Example

Formal Semantics of SQL

Equivalent Operational Semantics

Star as List of All Attributes

Renaming columns

Expressions as Values in Columns

Trick

Trick (II)

Example

Example (II)

Example (III)

Patterns

Example

Multirelation Queries

Example

Example (II)

Formal Semantics

Operational Semantics

Example

Explicit Tuple Variables

Example

Example (II)

Subqueries

Simplest Case

Simplest Case (II)

Simplest Case (III)

The IN Operator

Example

Example (II)

EXISTS

Example

Example (II)

Example (III)

Quantifiers

Example

Problem

Email: burt@umbc

Home Page: www.cs.umbc.edu/~burt