Integrity constraints (including key, referential and domain constraints) are unique features of database applications. Integrity constraints are crucial for ensuring accuracy and consistency of data in a database. It is important to perform integrity constraint enforcement (ICE) at the application level to reduce the risk of database corruption. We have conducted an empirical analysis of open-source PHP database applications and found that ICE does not receive enough attention in real-world programming practice. We propose an approach for automatic detection of ICE violations at the application level based on identification of code patterns. We define four patterns that characterize the structures of code implementing integrity constraint ...