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SQL Server add auto increment primary key to existing table
As the title, I have an existing table which is already populated with 150000 records. I have added an Id column (which is currently null).
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How to check if a column exists in a SQL Server table?
...HERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tableName', 'columnName') IS NOT NULL
BEGIN
-- Column Exists
END
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INNER JOIN ON vs WHERE clause
...It is generally considered more readable, especially when you join lots of tables.
It can also be easily replaced with an OUTER JOIN whenever a need arises.
The WHERE syntax is more relational model oriented.
A result of two tables JOINed is a cartesian product of the tables to which a filter is ...
How are virtual functions and vtable implemented?
...ons in C++":
Whenever a program has a virtual function declared, a v - table is constructed for the class. The v-table consists of addresses to the virtual functions for classes that contain one or more virtual functions. The object of the class containing the virtual function contains a virtual...
MYSQL Truncated incorrect DOUBLE value
...se I was not using apostrophes in where clause.
Like my query was
update table set coulmn1='something' where column2 in (00012121);
when I changed where clause to where column2 in ('00012121'); then the query worked fine for me.
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How to find the installed pandas version
...-dev
sphinx: 1.2.2
patsy: 0.3.0
dateutil: 1.5
pytz: 2012c
bottleneck: None
tables: 3.1.1
numexpr: 2.2.2
matplotlib: 1.4.2
openpyxl: None
xlrd: 0.9.3
xlwt: 0.7.5
xlsxwriter: None
lxml: 3.3.3
bs4: 4.3.2
html5lib: 0.999
httplib2: 0.8
apiclient: None
rpy2: 2.5.5
sqlalchemy: 0.9.8
pymysql: None
psycopg2:...
Safe characters for friendly url [closed]
...Or in other words: You may use any (non-control-) character from the ASCII table, except /, ?, #, [ and ].
This understanding is backed by RFC1738 - Uniform Resource Locators (URL).
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Can a class member function template be virtual?
...teresting techniques stemming from combining polymorphism and templates, notably so-called type erasure.
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Disable Laravel's Eloquent timestamps
... we don't want to add the updated_at / created_at fields to all of our tables as we have a logging class that does all this in more depth for us already.
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This Row already belongs to another table error when trying to add rows?
I have a DataTable which has some rows and I am using the select to filter the rows to get a collection of DataRows which I then loop through using foreach and add it to another DataTable, but it is giving me the error "This Row already belongs to another table". Here is the code:
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