Semantic errors in SQL queries: A quite complete list

Semantic Errors in SQL Queries

We investigate classes of SQL queries which are syntactically correct, but certainly not intended, no matter for which task the query was written. For instance, queries that are contradictory, i.e. always return the empty set, are quite often written in exams of database courses. Current database management systems, e.g. Oracle, execute such queries without any warning. In this paper, we try to...

Detecting Semantic Errors in SQL Queries

We investigate classes of SQL queries which are syntactically correct, but certainly not intended, no matter for which task the query was written. For instance, queries that are contradictory, i.e. always return the empty set, are quite often written in exams of database courses. Current database management systems, e.g. Oracle, execute such queries without any warning. In this paper, we explai...

Do You Know Sql? about Semantic Errors in Database Queries

We investigate classes of SQL queries which are syntactically correct, but certainly not intended, no matter for which task the query was written. For instance, queries that are contradictory, i.e. always return the empty set, are quite often written in exams of database courses. Current database management systems, e.g. Oracle, execute such queries without any warning. In this paper, we give s...

Semanti Errors in SQL Queries

Detecting Logical Errors in SQL Queries

Queries that are contradictory, i.e. always return the empty set, are quite often written in exams of database courses. Although such queries are obviously not intended, they are executed in current database management systems (e.g., Oracle) without any warning. Of course, questions like the satisfiability are in general undecidable, but we give a quite simple algorithm that can handle a surpri...