Sunday, July 9, 2006

sql normenclature

Clarity and brevity are the #1 and #2 goals of technical communication.

A stored function can serve as a "select ITEM", an "order-by-ATTRIBUTE", a "group-by-FIELD", or part of a "where-CRITERIA" or "having-PREDICATE" -- "criteria/predicate" are more precise than "condition".

A view and a sub-select can serve as a "from TARGET"

A forkey entry/value "references" a prikey entry/value.
3 forkeys (columns) can "refererence/point-to/refer-to" the same prikey.
A table can have 2 forkeys (columns) pointing to 2 prikeys, in 2 tables.

"20 rows, each containg 4 FIELDS" ---- Avoid "column" .

A column can "hold 14 ENTRIES / values " (Avoid "values" ) but only 9 "distinct values" including the special "null value".

The 14 entries include 2 "null ENTRIES / values" (Avoid "values" ) , so there are only 12 KNOWN-VALUES.

"Entry" has a more specific meaning. "2 null entries" sound better than "2 null values".

Many say "These 2 values are identical.", but It's clearer to say "These 2 RECORDS are identical" when you select several non-key columns.

"duplicate ENTRIES / RECORDS" ---- Avoid "values"

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