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SQL Server equivalent to MySQL enum data type?
Does SQL Server 2008 have a a data-type like MySQL's enum ?
5 Answers
5
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ALTER TABLE to add a composite primary key
...r table you will get an error when trying to drop it. In some versions of mysql the error message there was malformed (as of 5.5.17, this error message is still
alter table parent drop column id;
ERROR 1025 (HY000): Error on rename of
'./test/#sql-a04_b' to './test/parent' (errno: 150).
If you ...
Convert Unix timestamp into human readable date using MySQL
Is there a MySQL function which can be used to convert a Unix timestamp into a human readable date? I have one field where I save Unix times and now I want to add another field for human readable dates.
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Unable to verify leaf signature
...ity you can add the necessary certificates to the chain. First install ssl-root-cas package from npm:
npm install ssl-root-cas
This package contains many intermediary certificates that browsers trust but node doesn't.
var sslRootCAs = require('ssl-root-cas/latest')
sslRootCAs.inject()
Will add...
How big can a MySQL database get before performance starts to degrade
At what point does a MySQL database start to lose performance?
15 Answers
15
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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...doesn't have to sort the output, and GROUP BY by default does. However, in MySQL even a DISTINCT+ORDER BY might still be faster than a GROUP BY due to the extra hints for the optimizer as explained by SquareCog.
– rustyx
Jan 25 '15 at 15:03
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How to copy data from one table to another new table in MySQL?
I want to copy data from one table to another in MySQL.
11 Answers
11
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MySQL order by before group by
...pand on my comments about using a subquery to accurate return this data.
MySQL does not force you to GROUP BY every column that you include in the SELECT list. As a result, if you only GROUP BY one column but return 10 columns in total, there is no guarantee that the other column values which bel...
How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...DROP { [ CONSTRAINT ] constraint_name | COLUMN column } [ ,...n ]
For MySQL:
ALTER TABLE TableName
DROP COLUMN Column1,
DROP COLUMN Column2;
or like this1:
ALTER TABLE TableName
DROP Column1,
DROP Column2;
1 The word COLUMN is optional and can be omitted, except for RENAME...
SQL Server equivalent of MySQL's NOW()?
I'm a MySQL guy working on a SQL Server project, trying to get a datetime field to show the current time. In MySQL I'd use NOW() but it isn't accepting that.
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