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Error 1046 No database Selected, how to resolve?
...ell MySQL which database to use:
USE database_name;
before you create a table.
In case the database does not exist, you need to create it as:
CREATE DATABASE database_name;
followed by:
USE database_name;
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SQL Server SELECT LAST N Rows
...Feature also. A great example can be found here:
I am using the Orders table of the Northwind database... Now let us retrieve the Last 5 orders placed by Employee 5:
SELECT ORDERID, CUSTOMERID, OrderDate
FROM
(
SELECT ROW_NUMBER() OVER (PARTITION BY EmployeeID ORDER BY OrderDate DESC) AS Or...
Create Pandas DataFrame from a string
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FYI - pd.read_table() is an equivalent function, just slightly better nomenclature: df = pd.read_table(TESTDATA, sep=";").
– wkzhu
Dec 6 '17 at 23:17
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Good way to use table alias in Update statement?
I'm using SQL Server, and trying to update rows from within the same table. I want to use a table alias for readability.
2 ...
How to compute the similarity between two text documents?
...ion:
session.run(tf.global_variables_initializer())
session.run(tf.tables_initializer())
message_embeddings_ = session.run(similarity_message_encodings, feed_dict={similarity_input_placeholder: messages})
corr = np.inner(message_embeddings_, message_embeddings_)
print(corr)
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Set a DateTime database field to “Now”
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In SQL you need to use GETDATE():
UPDATE table SET date = GETDATE();
There is no NOW() function.
To answer your question:
In a large table, since the function is evaluated for each row, you will end up getting different values for the updated field.
So, if yo...
How do I view the full content of a text or varchar(MAX) column in SQL Server 2008 Management Studio
... this live SQL Server 2008 (build 10.0.1600) database, there's an Events table, which contains a text column named Details . (Yes, I realize this should actually be a varchar(MAX) column, but whoever set this database up did not do it that way.)
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UITableViewCell show white background and cannot be modified on iOS7
I've implemented a custom table view cell class that inherit from UITableViewCell . The tableview contains a background image, so I want cell's background to be transparent. It looks great before iOS7.
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Select values from XML field in SQL Server 2008
...alue('(/person//lastName/node())[1]', 'nvarchar(max)') as LastName
FROM [myTable]
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How do I stop Entity Framework from trying to save/insert child objects?
...everything, EF seems to be still trying to insert into some of the related tables. At this point, I'm ready to rip EF out and switch back to SQL which at least behaves sensibly. What a pain.
– Mark Micallef
Aug 22 '14 at 8:29
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