joe celkos sql puzzles answers

... Oracle, which I tried to translate into SQL-92 with mixed results The problem with the translation was that the Oracle version of SQL did not support the SQL- 92 standard OUTER JOIN syntax, and ... operation Answer #3 I got several answers in response to my challenge for a better solution to this puzzle Richard Romley of Smith Barney sent in the following SQL-92 solution It takes advantage ... just switched over from Paradox to Watcom SQL (now part of Sybase) The conversion of the legacy database was done by making each Paradox table into a Watcom SQL table, without any thought of normalization

Ngày tải lên: 21/01/2014, 08:20

... occurrences on the payroll How would you write this query in SQL- 89? In SQL- 92? In SQL- 99? Answer #1 SQL- 89 lacks the orthogonality that SQL- 92 has, so the best way is probably to build a VIEW ... problem is that for some SQL products, the self-joins are very expensive. This is probably the fastest answer on the old SQL products. Can you think of another way? Answer #2 In SQL-92, this is easy ... '1994-07-16' '1994-07-30' NULL Answer #1 If you only have an SQL-89 product instead of an SQL-92, you can do this with self-joins: SELECT S0.order_nbr, S0.sch_date, S0.sch_date,

Ngày tải lên: 21/01/2014, 08:20

... is always a solution, and (2) there is often more than one solution Doing this in SQL is really hard because SQL does not backtrack Remember that a stable marriage is not always a happy marriage ... again This is considerably faster than the combinatory explosion that SQL must generate and filter The only advantage with SQL—and it is weak—is that the algorithms for this problem will usually ... they both would rather be matched to someone else For example, let’s assume the husbands are (“Joe Celko,” “Brad Pitt”) and the wives are (“Jackie Celko,” “Angelina Jolie”) If Jackers got matched

Ngày tải lên: 26/01/2014, 08:20

... Keeping... into SQL programming His best-selling books include Joe Celko’s SQL for Smarties: Advanced SQL Programming, second edition; Joe Celko’s SQL Puzzles and Answers; and Joe Celko’s ... SQL programming His best-selling books include Joe Celko’s SQL for Smarties: Advanced SQL Programming, second edition; Joe Celko’s SQL Puzzles. .. 22 SIMILAR TO, 239 PRIMARY KEY constraint, ... 99, OLAP functions, 153 SQL- 2003, OLAP functions, 147 SQL for Smarties, 242 SQL puzzles absentees, 4–8 age ranges for products, 261–62 airlines and... most-read SQL authors in the world

Ngày tải lên: 26/01/2014, 08:20

... ISAM file in SQL You lose all the advantages of an abstract data model and SQL set-oriented programming, because you carry extra data and destroy the portability of code The early SQLs were based ... them into the same table These possible schemas are at least in 3NF They are given in shorthand SQL DDL (Data Declaration Language) without data type declarations Solution 1: CREATE TABLE R1 (flight, ... values into the encoding schemes for that column, as discussed in as discussed in Section 5.2 of SQL Programming Style, ISBN 0-12-088797-5, on encoding schemes. Trang 7A normalized database will

Ngày tải lên: 06/07/2014, 09:20

... procedure that will output the SQL code for a given value of (n) The obvious direct way to do a Swap() is to write a chain of UPDATE statements Remember that in SQL, the SET clause assignments ... END IF; END; Trang 10C H A P T E R3 Numeric Data in SQL S QL IS NOT A computational or procedural language; the arithmetic capability of SQL is weaker than that of any other language you have ... they are not quite the same 3.1 Numeric Types The SQL Standard has a wide range of numeric types The idea is that any host language can find an SQL numeric type that matches one of its own You

Ngày tải lên: 06/07/2014, 09:20

... 102 CHAPTER 3: NUMERIC DATA IN SQL Numbers in SQL are classified as either exact or approximate. An exact numeric value has a precision, ... operations, while SNaNs denote invalid operations. SQL has not accepted the IEEE model for mathematics for several reasons. Much of the SQL Standard allows implementation-defined rounding, ... Data Types Machine-level things like a BIT or BYTE data type have no place in SQL. SQL is a high-level language; it is abstract and defined without regard to physical implementation.

Ngày tải lên: 06/07/2014, 09:20

... Standard SQL also has a full set of operators for these data types The full syntax and functionality have not Trang 3124 CHAPTER 4: TEMPORAL DATA TYPES IN SQL yet been implemented in any SQL product, ... arithmetic in your SQL, but you might find that some library functions will let you do a better job than what you see here Please continue to check your manuals until the SQL Standard is implemented ... option is called the calendar date format Standard SQL uses this all-numeric “yyyy-mm-dd” format to conform to ISO-8601, which had Trang 44.2 SQL Temporal Data Types 125to avoid language-dependent

Ngày tải lên: 06/07/2014, 09:20

... KEY (name, status, from_date, to_date)); While nonsequenced duplicates are easy to prevent via SQL statements, such constraints are not that useful in practice The intuitive meaning of the above ... check constraint, or even one or more triggers, is required As a challenge, consider specifying in SQL a primary key constraint on a period-stamped valid-time table Then try specifying a referential ... the most natural analog of the nontemporal constraint, yet was the most challenging to express in SQL For the LotLocations table, the appropriate uniqueness constraint would be that feedyard_id,

Ngày tải lên: 06/07/2014, 09:20

... concerns the specific representation (deleting particular records) Conversely, the associated SQL statements for the current and sequenced variants are much more complex than the statement for ... current or sequenced modifications Nonsequenced modifications, while generally easier to express in SQL, are rare For those who want a challenge, alter the above modification statements to ensure

Ngày tải lên: 06/07/2014, 09:20

... in SQL Server. 174 CHAPTER 5: CHARACTER DATA TYPES IN SQL 5.3 Common Vendor Extensions The original SQL-89 standard did not define any functions for CHAR(n) data types. Standard SQL ... alike. SQL products often have a Soundex algorithm in their library functions. It is also possible to compute a Soundex in SQL, using string functions and the CASE expression in Standard SQL. ... implement them outside of SQL. Many vendors also have functions that will format data for display by converting the internal format to a text string. A vendor whose SQL is tied to a 4GL is much

Ngày tải lên: 06/07/2014, 09:20

... criticisms apply to any system that supports SQL-style NULL s, not just to SQL Server specifically.)” 186 CHAPTER 6: NULLS: MISSING DATA IN SQL SQL takes the middle ground and has a single ... you have to say (x IS [NOT] NULL) in SQL and not use (x = NULL) instead. Table 6.1 shows the tables for the three operators that come with SQL. Table 6.1 SQL’s Three Operators x NOT ================== ... tokens for missing values at all. Standard SQL uses one token, based on Dr. Codd’s original relational model. Perhaps Dr. Codd was right—again. In Standard SQL, adding ROLLUP and CUBE

Ngày tải lên: 06/07/2014, 09:20

... Samet Joe Celko’s SQL for Smarties: Advanced SQL Programming, Third Edition Joe Celko Moving Objects Databases Ralf Hartmut Güting and Markus Schneider Joe Celko’s SQL Programming Style Joe Celko Data ... Jim Gray, Microsoft Research Joe Celko’s Analytics and OLAP in SQL Joe Celko Data Preparation for Data Mining Using SAS Mamdouh Refaat Querying XML: XQuery, XPath, and SQL/ XML in Context Jim Melton ... standard was SQL- 86, and the SQL- 92 standard was a design goal for the database vendors. Today, most vendors have gotten most of SQL- 92 into their products. The design goal is now the SQL- 99 standard’s...

Ngày tải lên: 21/01/2014, 08:20