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Difference between “read commited” and “repeatable read”
...nd consider you have a simple task like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any da...
Download old version of package with NuGet
...t-Package -ListAvailable [-Source X] -Filter Common.Logging -AllVersions | select version, dependencies (or '| get-member' to see all the properties)
– Curtis Yallop
Jan 25 '13 at 21:49
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Select between two dates with Django
I am looking to make a query that selects between dates with Django.
4 Answers
4
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Maximum Year in Expiry Date of Credit Card
...orget that in most browsers you can still key in the number and it'll auto select.
– Kevin Wiskia
Mar 22 '11 at 19:44
1
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How do I find numeric columns in Pandas?
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You could use select_dtypes method of DataFrame. It includes two parameters include and exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numer...
Copy/duplicate database without using mysqldump
...the references, you can run the following to copy the data:
INSERT INTO x SELECT * FROM other_db.y;
If you're using MyISAM, you're better off to copy the table files; it'll be much faster. You should be able to do the same if you're using INNODB with per table table spaces.
If you do end up doin...
Run PostgreSQL queries from the command line
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psql -U username -d mydatabase -c 'SELECT * FROM mytable'
If you're new to postgresql and unfamiliar with using the command line tool psql then there is some confusing behaviour you should be aware of when you've entered an interactive session.
For example, ...
Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
...
Insert all values of a table into another table in SQL
.... But the insert statement accepts values, but i would like it to accept a select * from the initial_Table. Is this possible?
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SQL Server query - Selecting COUNT(*) with DISTINCT
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Count all the DISTINCT program names by program type and push number
SELECT COUNT(DISTINCT program_name) AS Count,
program_type AS [Type]
FROM cm_production
WHERE push_number=@push_number
GROUP BY program_type
DISTINCT COUNT(*) will return a row for each unique count. What you want is C...