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Compare if two variables reference the same object in python
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In the example, x is z returns False. But if x and z are assigned the same values instead of lists (for example x, z = 13, 13) then x is z returns True. Why is that?
– Bill
Dec 13 '15 ...
Select datatype of the field in postgres
How do I get datatype of specific field from table in postgres ?
For example
I have the following table,
student_details (
stu_id integer,
stu_name varchar(30 ),
joined_date timestamp
);
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How can I do an UPDATE statement with JOIN in SQL Server?
I need to update this table in SQL Server with data from its 'parent' table, see below:
16 Answers
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Cannot insert explicit value for identity column in table 'table' when IDENTITY_INSERT is set to OFF
I have the below error when I execute the following script. What is the error about, and how it can be resolved?
21 Answers...
Why is $$ returning the same id as the parent process?
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$$ is defined to return the process ID of the parent in a subshell; from the man page under "Special Parameters":
$ Expands to the process ID of the shell. In a () subshell, it expands to the process ID of the current shell,...
Get the new record primary key ID from MySQL insert query?
Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
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Rails: Adding an index after adding column
Suppose I created a table table in a Rails app. Some time later, I add a column running:
5 Answers
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python pandas dataframe to dictionary
I've a two columns dataframe, and intend to convert it to python dictionary - the first column will be the key and the second will be the value. Thank you in advance.
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jQuery ID starts with
I am trying to get all elements with an id starting with some value. Below is my jQuery code. I am trying to use a JavaScript variable when searching for items. But it does not work. What am I missing below? So the id 'value' am searching is the value of the clicked element
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When to use .First and when to use .FirstOrDefault with LINQ?
...'d want to use .First and when you'd want to use .FirstOrDefault with LINQ.
14 Answers
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