Talk:Select (SQL)

message: Someone started a policy debate concerning the use of source code in articles, that seems to directly impact this (and possibly other Database articles).  See below for details:
I have opened a debate on the use of source code and other examples in Wikipedia articles. It seems that many pieces of example source code etc. currently in Wikipedia violate Wikipedia policy, so we need to either clarify or change the situation. Depending on the result of the discussion, this may result in a number of source code examples being summarily removed from computing articles!
Please reply there, not here, if you wish to contribute.—greenrd 10:50, 18 May 2007 (UTC)
replies: text: That discussion is now archived at Wikipedia_talk:Attribution/Archive_17#Explicit mention of examples (source code, math, etc.). - Jmabel | Talk 23:29, 21 January 2008 (UTC)
thread_title:  POLICY DEBATE: Use of source code and other examples in articles 

message: Although this may vary between implementations of SQL, is it worth explaining that SELECT * from xxx does have performance impacts on the way that the database has to work out the table size on the fly, whereas explicit declaration is quicker?
::I don't think that's really a factor--working out the table size on the fly shouldn't have a significant impact, since SQL implementations that follow ISO standards store metadata about the tables involved in the database anyway. Also SELECT * could perform worse in some situations or better in other situations.  For instance, SELECT * returns every column in the table--even columns that may not be needed for the task at hand which could impact performance negatively. On the other hand, an optimized SQL query engine may be able to optimize the way in which it retrieves rows by using an index to retrieve rows when one is available, which can be more efficient than a simple table scan in some implementations. It's really implementation-specific behavior. SqlPac (talk) 01:25, 24 March 2008 (UTC)
thread_title:  Performance 

message: No discussion of nested selects. No link to any in-depth discussion on Wikibooks, though I presume one exists. External links provided are almost useless: one is to a decent overall article on Oracle, but it's in Spanish (and it isn't particularly about the Select statement). The other is to a short manual page on the Select statement that doesn't seem to have much significant content not already in the article. - Jmabel | Talk 23:26, 21 January 2008 (UTC)
replies: text: WP:BB  SqlPac (talk) 03:26, 21 March 2008 (UTC)
thread_title:  Pretty minimal 

message: In the opening for the article it states that SELECT is the most commonly used DML command.  SELECT is actually not a DML statement.  The ISO 9075:2003 standard specifically divides up the landscape like this:
 Data-Language Statements
 |
 +----Query Statements
 |      |
 |      +----Multirow SELECT Statements
 |
 +----Data Manipulation Language
        |
        +----INSERT, UPDATE, DELETE, MERGE, Cursor Statements
        |
        +----Single-row SELECT INTO Statement
In all fairness, the single-row SELECT INTO statement is included in DML, but multirow SELECT statement is not. SqlPac (talk) 01:33, 24 March 2008 (UTC)
thread_title:  SELECT <> DML 

message: I added a couple references and accordingly removed the Unreferenced|date=May 2007 & September 2007 tags. If anyone with more sql knowledge thinks there is still unreferenced content by all means point out where or re-add the tags --Faradayplank (talk) 05:30, 24 March 2008 (UTC)
replies: text: "In most applications, SELECT is the most commonly used Data Manipulation Language (DML) command." No reference is given.  ISO/IEC 9075:2003 (the SQL:2003 standard) can be used as a reference that contradicts this statement. SqlPac (talk) 22:52, 24 March 2008 (UTC)
thread_title:  References 

message: Maybe mention that one can do
 SELECT col1, col1 FROM bla;
but not
 SELECT *, col1 FROM bla;
apparently for no good reason. Jidanni (talk) 04:42, 28 March 2009 (UTC)
thread_title: SELECT *, col1

message: Another example would be the "SAMPLE n" format used by Unidata (likely other PICK style systems, most of whom have a SQL interface)
66.46.252.68 (talk) 16:43, 5 March 2010 (UTC)
thread_title:  PICK-style? 

message: The first example in Window functions isn't very good: summing the population partitioning by city would only make sense on a "suburbs" table. A better example would be to sum the salary partitioning by department on an "employees" table. Colin 't Hart (talk) 14:00, 8 August 2013 (UTC)
thread_title: Window functions first example

message: i got here by following a link for "the 'select into' variant" but that is not described here.  — Preceding unsigned comment added by 204.8.27.140 (talk) 18:44, 4 November 2013 (UTC)
thread_title:  "SELECT INTO" 

message: What's the purpose of this section? Why add beginner SQL coding tips, labeled as T-SQL "feature"?  — Preceding unsigned comment added by Fjerdingen (talk • contribs) 20:46, 24 May 2017 (UTC)
thread_title:  "Generating Data in T-SQL"