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Advantages and disadvantages of GUID / UUID database keys
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Hear hear! Love your SQL comparison page btw. Extremely useful. The only thing I miss is a changelog.
– Henrik Gustafsson
Sep 16 '08 at 20:40
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Can you use an alias in the WHERE clause in mysql?
...ll not work, in which case you'll need to use a HAVING clause.
From the MySQL Manual:
It is not allowable to refer to a
column alias in a WHERE clause,
because the column value might not yet
be determined when the WHERE clause
is executed. See Section B.1.5.4,
“Problems with Column...
is of a type that is invalid for use as a key column in an index
... on maximum index row size. technet.microsoft.com/en-us/library/ms176089(v=sql.100).aspx
– Daniel Renshaw
May 15 '14 at 11:50
1
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Psql list all tables
I would like to list all tables in the liferay database in my PostgreSQL install. How do I do that?
6 Answers
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How to see the CREATE VIEW code for a view in PostgreSQL?
...s there an easy way to see the code used to create a view using the PostgreSQL command-line client?
6 Answers
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mysql: see all open connections to a given database?
With administrative permissions im mysql, how can I see all the open connections to a specific db in my server?
8 Answers
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Transaction isolation levels relation with locks on table
...B client won't have the updated data.
REPEATABLE READ - lock on a block of SQL(which is selected by using select query). This means B reads the data under some condition i.e. WHERE aField > 10 AND aField < 20, A inserts data where aField value is between 10 and 20, then B reads the data again ...
Select mySQL based only on month and year
I have a column in my mySQL DB that has some rows. One of this row is a DATE, like this: 2012-02-01
12 Answers
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How do I create a simple 'Hello World' module in Magento?
...lated topics, but for now, I don't. I will, however, briefly speak to your SQL question.
Magento uses an EAV database architecture. Whenever possible, try to use the model objects the system provides to get the information you need. I know it's all there in the SQL tables, but it's best not to thin...
WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
...he difference is in terms of scope. See READUNCOMMITTED and NOLOCK in the SQL Server documentation here:
http://technet.microsoft.com/en-us/library/ms187373.aspx
For TRANSACTION ISOLATION LEVEL:
http://technet.microsoft.com/en-us/library/ms173763.aspx
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