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SQL SELECT speed int vs varchar
I'm in the process of creating a table and it made me wonder.
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How to use index in select statement?
Lets say in the employee table, I have created an index(idx_name) on the emp_name column of the table.
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Which data type for latitude and longitude?
... want to store latitude and longitude values in PostgreSQL 9.1.1 database table. I will calculate distance between two points, find nearer points by using this location values.
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Alter a MySQL column to be AUTO_INCREMENT
I’m trying to modify a table to make its primary key column AUTO_INCREMENT after the fact. I have tried the following SQL, but got a syntax error notification.
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MySQL error: key specification without a key length
I have a table with a primary key that is a varchar(255). Some cases have arisen where 255 characters isn't enough. I tried changing the field to a text, but I get the following error:
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How to generate a range of numbers between two numbers?
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@Rafi the v(n) and hundreds(n) etc are table and column names/aliases
– Twon-ha
Oct 8 '19 at 14:13
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Accessing a Dictionary.Keys Key through a numeric index
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seems to not work with HashTable System.Collections.ICollection' does not contain a definition for 'ElementAt' and no extension method 'ElementAt' accepting a first argument of type 'System.Collections.ICollection' could be found
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horizontal scrollbar on top and bottom of table
I've a very large table on my page. So I decided to put a horizontal scrollbar on the bottom of the table. But I would like this scrollbar to be also on top on the table.
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Adding a column to an existing table in a Rails migration
...e the add_column line completely (that code is trying to add a column to a table, before the table has been created, and your table creation code has already been updated to include a t.string :email anyway).
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Table row and column number in jQuery
How do I get the row and column number of the clicked table cell using jQuery, i.e.,
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