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SQL to find the number of distinct values in a column
...aggregate function:
SELECT COUNT(DISTINCT column_name) AS some_alias FROM table_name
This will count only the distinct values for that column.
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Thread-safe List property
...em.ServiceModel.dll (which is part of the client profile but not of the portable class library).
Hope that helps.
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Add new column with foreign key constraint in one command
...to add the column and the foreign key constraint using two separate ALTER TABLE commands:
12 Answers
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Disable ONLY_FULL_GROUP_BY
...For instance, insert (below the [mysqld] section) sql_mode = "STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
– Vincent Pazeller
Nov 22 '16 at 10:44
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Altering a column to be nullable
I want to alter a table column to be nullable. I have used:
10 Answers
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SQL update trigger only when column is modified
...oRepair <> I.QtyToRepair
END
END
2- Use Join between Inserted table and deleted table
ALTER TRIGGER [dbo].[tr_SCHEDULE_Modified]
ON [dbo].[SCHEDULE]
AFTER UPDATE
AS BEGIN
SET NOCOUNT ON;
UPDATE SCHEDULE
SET modified = GETDATE()
, ModifiedUser = SUSER_NAME...
CSS display: table min-height not working
...e know I can make min-height work with the latest browsers? I am using CSS tables and it seems to ignore min-height.
4 Answ...
Sequelize Unknown column '*.createdAt' in 'field list'
...he error is that you have timestamps enabled in sequelize, but your actual table definitions in the DB do not contain a timestamp column.
When you do user.find it will just do SELECT user.*, which only takes the columns you actually have. But when you join, each column of the joined table will be a...
Detect Windows version in .net
...nment is running in, check out this library.
Important note: if your executable assembly manifest doesn't explicitly state that your exe assembly is compatible with Windows 8.1 and Windows 10.0, System.Environment.OSVersion will return Windows 8 version, which is 6.2, instead of 6.3 and 10.0! Sourc...
What are best practices that you use when writing Objective-C and Cocoa? [closed]
...lass? That is especially true in an environment like the iPhone.
3.5) In table cells, make every element (including the cell itself) opaque for performance. That means setting the appropriate background color in everything.
3.6) When using an NSURLConnection, as a rule you may well want to implem...