SQL PROGRAMMING STYLE- P13 doc
SQL PROGRAMMING STYLE- P13 doc
... specifications were
never explained beyond that. He posted a pseudocode
program in T -SQL dialect, which would translate into Standard
SQL pseudocode something like this:
CREATE PROCEDURE TapeFileRoutine()
BEGIN
... overwhelming reason is ignorance
of SQL and old habits. The cursors in SQL are modeled after tape file
semantics, and people know that kind of procedural programmin...
SQL PROGRAMMING STYLE- P19 docx
... predicates or
CASE expressions.
As an example of a horrible misuse of SQL, Chris White posted a
procedure that built dynamic SQL that would then build a report. Aside
from the obvious violations ... what you actually want. The other set
operations in SQL- 92, EXCEPT [ALL], and INTERSECT [ALL] are not
widely available yet.
6.11 Testing SQL
When you are first writing a schema, you wi...
SQL PROGRAMMING STYLE- P21 docx
... score means and
why it is incremented.
In Standard SQL, a comment begins with two dashes ( ) and ends
with a new line, because the first SQL engines were on IBM mainframes
and used punchcards. ... brackets. They are a
better choice.
SQL programmers do not like to put comments in their code, not
even redundant or useless ones. My guess is that because SQL does a lot
of work in one...
SQL PROGRAMMING STYLE- P22 doc
...
6.2.3 Avoid Redundant Expressions
Rationale:
Most modern SQL engines are pretty smart. This was not always the case,
so older SQL programmers will sometimes add redundant predicates to a ... OR-ed predicates
Rationale:
The IN() predicate was first introduced in the Pascal programming
language. In SQL it has two forms; the list and the subquery. The list
form has a comma-separa...
SQL PROGRAMMING STYLE- P27 doc
... passes.
The most common use of concatenation codes is in keyword lists in
the header records of documents in textbases. The author or librarian
assigns each article in the system a list of keywords
SQL PROGRAMMING STYLE- P33 docx
... really fast on the current release of my SQL
software?
A1: Sure, if I want to lose all of the advantages of an abstract data model,
SQL set-oriented programming, carry extra data, and destroy ... faster and easy to program.
A2: This is an implementation problem that the SQL engine can handle.
For example, Teradata is a SQL designed for very large database (VLDB)
applications that...
SQL PROGRAMMING STYLE- P35 docx
... the actual problem.
Exceptions:
If your SQL product supports the SIMILAR TO predicate (a version of
grep() based on the POSIX standard in Standard SQL) , then you might
consider having a longer ...
Table Declaration
Rationale:
These constraints are not yet well supported in SQL products, but they
are legal SQL- 92 syntax. Their predicates involve the entire table as a
whole...
SQL PROGRAMMING STYLE- P37 doc
... FONTS, PUNCTUATION, AND SPACING
2.8 Indentation
When you have to indent in block-structured 3GL programming
languages, use three spaces. A single space is too short to be read as
anything but ... mechanical reasons.
That became the definition when we moved to electronic terminals.
The rule for SQL is that rivers override what we were doing in the old
3GL languages.
Rationale:...
SQL PROGRAMMING STYLE- P38 docx
...
Rational:
SQL allows you to skip some reserved words and to abbreviate others.
Try to use the full forms to document the program. This is a good thing
in COBOL, and it works in SQL as well.
For ... Standard
SQL is consistent and clear about aliases, views, and derived tables, as
well as a highly orthogonal language.
If the UPDATE clause could take an alias, according to the Standar...
SQL PROGRAMMING STYLE- P39 docx
... SECTION | SELECT | SESSION
| SESSION_USER | SET
| SIZE | SMALLINT | SOME | SPACE | SQL | SQLCODE | SQLERROR |
SQLSTATE
| SUBSTRING | SUM | SYSTEM_USER
| TABLE | TEMPORARY | THEN | TIME | TIMESTAMP ... have to wrap exceptionally long lines. This is not as big a
problem in a concise language like SQL as it was in a verbose language
like COBOL.
2.1 Typography and Code 29
| MATCH...
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