Finite model theory

Finite model theory has its origins in classical model theory but owes its systematic development to research from complexity theory. The text presents the main results of descriptive complexity theory, the connection between axiomatizability of classes of finite structures and their complexity with respect to time and space bounds. The logics that are important in this context include fixed point logics, transitive closure logics and also certain infinitary languages; their model theory is studied in detail. Other topics include DATALOG languages, quantifiers and oracles, 0-1 laws, and optimization and approximation problems. The book is written in such a way that the representative parts on the model theory and descriptive complexity theory may be read independently.