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How to turn IDENTITY_INSERT on and off using SQL Server 2008?
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Via SQL as per MSDN
SET IDENTITY_INSERT sometableWithIdentity ON
INSERT INTO sometableWithIdentity
(IdentityColumn, col2, col3, ...)
VALUES
(AnIdentityValue, col2value, col3value, ...)
SET IDENTITY_INSERT sometableWithIdentity OFF
The complete error messa...
resizes wrong; appears to have unremovable `min-width: min-content`
...nge the display property of the fieldset to one of the following values:
table-cell (recommended)
table-column
table-column-group
table-footer-group
table-header-group
table-row
table-row-group
Of these, I recommend table-cell. Both table-row and table-row-group prevent you from changing width, ...
Why is rbindlist “better” than rbind?
I am going through documentation of data.table and also noticed from some of the conversations over here on SO that rbindlist is supposed to be better than rbind .
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Google Docs/Drive - number the headings
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If you want something more easy, there is a Google Add-On called "Table of Contents" that will allow you to number your headings.
To install this add-on:
Click on the Add-Ons > Get Add-Ons.
Click on the "Table of Contents" icon or search for this addon to install it
Then your ...
Rails :include vs. :joins
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.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all...
SQL SELECT speed int vs varchar
I'm in the process of creating a table and it made me wonder.
9 Answers
9
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difference between primary key and unique key
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Primary Key:
There can only be one primary key in a table
In some DBMS it cannot be NULL - e.g. MySQL adds NOT NULL
Primary Key is a unique key identifier of the record
Unique Key:
Can be more than one unique key in one table
Unique key can have NULL values
It can be a can...
Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...012-04-10, Milestone 8)
Previously, at most one TIMESTAMP column per table could be
automatically initialized or updated to the current date and time.
This restriction has been lifted. Any TIMESTAMP column definition can
have any combination of DEFAULT CURRENT_TIMESTAMP and ON UPDATE
C...
How to store a list in a column of a database table
...hrdad's answer to a related question , I get it that a "proper" database table column doesn't store a list. Rather, you should create another table that effectively holds the elements of said list and then link to it directly or through a junction table. However, the type of list I want to creat...
Best way to strip punctuation from a string
...g.punctuation))
It's performing raw string operations in C with a lookup table - there's not much that will beat that but writing your own C code.
If speed isn't a worry, another option though is:
exclude = set(string.punctuation)
s = ''.join(ch for ch in s if ch not in exclude)
This is faster...