SQL PROGRAMMING STYLE- P32 pptx

... and then “Obtaining Permissions.” Library of Congress Cataloging-in-Publication Data Application submitted. ISBN: 0-1 2-0 8879 7-5 For information on all Morgan Kaufmann publications, visit our ... types: in SQL Server, DATETIME (their name for TIMESTAMP data type) is a binary number internally (UNIX -style system clock representation), but TIMESTAMP is a string of digits in DB2...

Ngày tải lên: 10/04/2014, 09:40

Ngày tải lên: 06/07/2014, 23:20

... tables, 63 SQL 4GLs, 151, 152 bad programming in, 184–89 as declarative language, 193 Dynamic, 168–70 injection, 169–70 Standard, 4, 5, 6, 7, 118 testing, 130–31 thinking in, 183–95 SQL- 92 CASE ... 3 quoted identifiers, 5 string operators, 108 SQL- 99, 3 Stamp coupling, 156 Standard functions, 108 Standard Industrial Classification (SIC), 14 Standard SQL case-sensitivity rules, 6, 7...

Ngày tải lên: 06/07/2014, 23:20

... system, 89–90 Display, 96 Domain-Key Normal Form (DKNF), 62–63 DROP TABLE statement, 67 Dynamic SQL, 168–70 purpose, 168 in stored procedures, 169 E Electronic data interchange (EDI) files,

Ngày tải lên: 06/07/2014, 23:20

... about Student Programming Practices,” Structured Programming , Fall 1989, p. 215. Celko, J. SQL for Smarties (3rd ed.). San Francisco: Morgan-Kaufmann, 2005. Celko, J. SQL Puzzles ... of Programming Style . Boston: McGraw-Hill, 1982. Ledgard, H. Programming Prover bs. Rochelle Park, NJ, Hayden Books, 1975. Ledgard, H., and L. J. Chmura. Fortran with Style:...

Ngày tải lên: 06/07/2014, 23:20

... the count is redundant; SQL is orthogonal, and the scalar subquery can be used wherever the scalar variable is used. Rows are not records and columns are not fields. SQL is a declarative language, ... TIMESTAMP,—null means current CHECK(in_time < out_time), PRIMARY KEY (user_id, in_time)); Many new SQL programmers are scared of NULLs, but this is a good use of them. We do not...

Ngày tải lên: 06/07/2014, 23:20

... used SQL/ PSM to mimic the classic COBOL program for this kind of summary. Without repeating a dozen columns again, a set-oriented solution is this: CREATE PROCEDURE SurveySummary() LANGUAGE SQL BEGIN DELETE ... original schema lacked keys and constraints that had to be added to give us this: 10.1 Bad Programming in SQL and Procedural Languages 187 but it at least follows the...

Ngày tải lên: 06/07/2014, 23:20

... procedural programming! SQL will not make up for a lack of programming skills. In fact, the bad effects of mimicking 3GL languages in SQL are magnified. The optimizers and compilers in SQL engines ... reasoning. 10.1 Bad Programming in SQL and Procedural Languages As an example of not learning any relational approaches to a problem, consider a posting in the comp.databases...

Ngày tải lên: 06/07/2014, 23:20

... tell what is good and what is bad in SQL. The procedural programmers had a deterministic environment in which the same program ran the same way every time. SQL decides how to execute a query ... front did not know this. Would you like to pick which four children will die because of sloppy programming? See what we mean by the last sentence in Ledgard’s quote? 9.6.2 Save Your First ....

Ngày tải lên: 06/07/2014, 23:20

... almost write itself. 9.2 Add the Words “Set of All…” in Front of the Nouns The big leap in SQL programming is thinking in sets and not in process steps that handle one unit of data at a time. ... still get multiple couples on the dance floor. This is where some experience with SQL helps. One of the customary programming tricks is to use a self-join to get a ranking of elements...

Ngày tải lên: 06/07/2014, 23:20

... following statement is the first impulse of most new SQL programmers, but it does not work. CREATE PROCEDURE IncreasePrices() LANGUAGE SQL DETERMINISTIC BEGIN UPDATE Books SET price = price ... CREATE TABLE Sequence (seq INTEGER NOT NULL PRIMARY KEY); CREATE PROCEDURE MakeSequence() LANGUAGE SQL DETERMINISTIC INSERT INTO Sequence (seq) SELECT hundred * 100 + ten * 10 + unit + 1 FR...

Ngày tải lên: 06/07/2014, 23:20

... 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...

Ngày tải lên: 06/07/2014, 23:20

... revolution and have reverted back to ad hoc programming but call it “extreme” or “agile” these days to make sloppy programming sound better. In classic structured programming, you have three control ... do, and it is why SQL is also known as a functional language. Procedural, communicational, informational, and functional cohesion are a bit more complicated in SQL than in 3GL pro...

Ngày tải lên: 06/07/2014, 23:20

... table quickly collects garbage. CHAR(n) data often has advantages for access and storage in many SQL products. Numeric encodings can take advantage of arithmetic operators for ranges, check digits, ... CHECK (CASE WHEN code_type = <type 1> AND <validation 1> THEN 1 —assume that your SQL product can support a huge CASE expression WHEN code_type = <type n> 5.3 Gen...

Ngày tải lên: 06/07/2014, 23:20

... example of having a column in a table change domain on the fly on September 29, 2004, on the SQL Server programming newsgroup. His goal was to keep football statistics; this is a simplification ... show about Bell Labs inventing C++ and OO programming for us, and we got to ask questions. One of the questions was how we should put OO stuff into SQL. His answer was that Bell Labs, w...

Ngày tải lên: 06/07/2014, 23:20