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MySQL: multiple tables or one table with many columns?
... user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases have a limit on the number of columns per table, but I wouldn't worry about it in normal cases, and you can ...
td widths, not working?
...utanyspaces), the cell will stretch nevertheless, unless your CSS contains table-layout: fixed for the table.
EDIT
As kristina childs noted on her answer, you should avoid both the width attribute and using inline CSS (with the style attribute). It's a good practice to separate style and structure...
Simple Pivot Table to Count Unique Values
This seems like a simple Pivot Table to learn with. I would like to do a count of unique values for a particular value I'm grouping on.
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WITH CHECK ADD CONSTRAINT followed by CHECK CONSTRAINT vs. ADD CONSTRAINT
...re the constraint is enabled even if the default constraint behavior for a table is changed.
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Eliminate extra separators below UITableView
When I set up a table view with 4 rows, there are still extra separators lines (or extra blank cells) below the filled rows.
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Add a column with a default value to an existing table in SQL Server
How can I add a column with a default value to an existing table in SQL Server 2000 / SQL Server 2005 ?
41 Answers
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MySQL: Fastest way to count number of rows
...eyword after SELECT:
SELECT SQL_CALC_FOUND_ROWS [needed fields or *] FROM table LIMIT 20 OFFSET 0;
After you have selected needed rows, you can get the count with this single query:
SELECT FOUND_ROWS();
FOUND_ROWS() has to be called immediately after the data selecting query.
In conclusion,...
Difference between Hive internal tables and external tables?
Can anyone tell me the difference between Hive's external table and internal tables.
I know the difference comes when dropping the table. I don't understand what you mean by the data and metadata is deleted in internal and only metadata is deleted in external tables.
Can anyone explain me in terms o...
How to delete a row by reference in data.table?
My question is related to assignment by reference versus copying in data.table . I want to know if one can delete rows by reference, similar to
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PostgreSQL “DESCRIBE TABLE”
How do you perform the equivalent of Oracle's DESCRIBE TABLE in PostgreSQL (using the psql command)?
22 Answers
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