The author has written this SQL-help in his free time because a quick and permanently online SQL-tutorial was needed. This is only a part of the whole SQL-standart, for more information about its implementations on different database systems please contact the software manyfacturers. The "Standard-SQL", first developed by IBM, was improved by software firms that develop relational database management systems (RDBMS). But all of this improvements can not be discussed in an brief help file. The small table after the command/keyword indicates in some cases, in wich system this command/keyword is implemented.
This document is not an official publication and is provided "as is". This document is not a full technical documentation and not completely error free. There is no warranty of any kind for errors in comercial or public projects, which result from wrong or wrong understanded descriptions in this pages.