Databases
Database Analogies
Collected by Xiaoying Tu — Textbook Beaulieu, A. (2009). Learning SQL. 2 ed. O'Reilly.
Data storage and indexing
Within-Database
Helps readers understand the mechanism of joining more than two tables
| Symbol | Concept |
|---|---|
| snowball | the "intermediate table" after joining each additional table |
The fact that each additional table is joined with the intermediate resulting table, just like the snowball gets bigger when rolling down the hill.
One way to think of a query that uses three or more tables is as a snowball rolling down a hill. The first two tables get the ball rolling, and each subsequent table gets tacked on to the snowball as it heads downhill. You can think of the snowball as the intermediate result set, which is picking up more and more columns as subsequent tables are joined.
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A notional machine is a pedagogic device to assist the understanding of some aspect of programs or programming. To something along the lines of A notional machine is a pedagogical tool designed to support the understanding of programs, programming, and other aspects of computing such as databases.
