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Wikipedia:Reference desk/Archives/Computing/2018 November 18

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November 18

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Access to repair manuals

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What laptop or smartphone manufacturers provide generally good repair manuals? I mean legally accessible and well-written? — Preceding unsigned comment added by 31.4.149.178 (talk) 01:08, 18 November 2018 (UTC)[reply]

Many. You should be more specific about your smartphone model. Ruslik_Zero 20:26, 18 November 2018 (UTC)[reply]
It is about basic knowledge. An repair manual only guides you in special steps of the specific model. Much of it is to know how buck converters work an in witch way they fail. On the other hand it is just replacing components after identifying the failure. It is also removing optional failed components which fail the machine form start up. --Hans Haase (有问题吗) 07:54, 25 November 2018 (UTC)[reply]

SQL Query without FROM clause

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Hi all,

The article From (SQL) mentions that " From clauses are very common" and that "FROM is an SQL reserved word in the SQL standard". Could you please help me to understand how to implement a query without the From clause? As far as I know this can be done, I just don't know under which conditions (kind of databases, general form, limitations, ...). Many thanks for the help. Best regards --Hundsrose (talk) 17:19, 18 November 2018 (UTC)[reply]

UPDATE and INSERT queries do not use FROM. If you mean in a SELECT query, as long at the statement does not refer to a table you could run one without a FROM clause:
SELECT CONCAT("No"," ","FROM"," ","clause") AS text;
--Canley (talk) 21:20, 18 November 2018 (UTC)[reply]
@Canley:: Thanks a lot. Exactly what I needed. I'd love to put this additional information as a new section in the from article. What's your opinion about that? Best regards --Hundsrose (talk) 10:22, 20 November 2018 (UTC)[reply]
There is already a "Requirement" section in that article which says "many relational DBMS implementations may not require it for selecting a single value, or single row", with an example. --Canley (talk) 12:28, 22 November 2018 (UTC)[reply]
You're right. Thanks a lot. --Hundsrose (talk) 17:36, 22 November 2018 (UTC)[reply]