Easy Steps to a Complete Understanding of SQL

Re:Easy Steps to a Complete Understanding of SQL by ExpiredLink on Tuesday September 03, 2013 @11:39AM (#6321551)

> If a has 3 columns and b has 5 columns, then the "output table" will have 8 (3 + 5) columns. The records contained in this combined table reference are those of the cross product / cartesian product of a x b.

This is where the easy steps become hard for real noobs.

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Re:Easy Steps to a Complete Understanding of SQL by pbhjpbhj on Tuesday September 03, 2013 @11:22PM (#6325350)

A graphical example of a Cartesian join - http://web.utk.edu/sas/OnlineTutor/1.2/en/60477/m71/m71_3.ht....

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Re:Easy Steps to a Complete Understanding of SQL by julochrobak on Wednesday September 04, 2013 @03:11AM (#6326080)

here are some other graphical illustrations of the operators from relational algebra - http://bandilab.org/bandicoot-algebra.pdf

It's focusing on bandicoot language, but concepts are taken from the relational algebra. It should match the logic of SQL.

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