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How to drop a table if it exists?
The table name is Scores .
14 Answers
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Add horizontal scrollbar to html table
Is there a way to add a Horizontal scrollbar to an HTML table? I actually need it to be scrollable both vertically and horizontally depending on how the table grows but I can't get either scrollbar to appear.
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How do you list the primary key of a SQL Server table?
Simple question, how do you list the primary key of a table with T-SQL? I know how to get indexes on a table, but can't remember how to get the PK.
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Sql Server 'Saving changes is not permitted' error ► Prevent saving changes that require table re-cr
When I create a table in SQL Server and save it, if I try to edit the table design, like change a column type from int to real, I get this error:
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SQL Server: Is it possible to insert into two tables at the same time?
My database contains three tables called Object_Table , Data_Table and Link_Table . The link table just contains two columns, the identity of an object record and an identity of a data record.
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Display names of all constraints for a table in Oracle SQL
I have defined a name for each of the constraint for the multiple tables that I have created in Oracle SQL.
6 Answers
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CROSS JOIN vs INNER JOIN in SQL
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Cross join does not combine the rows, if you have 100 rows in each table with 1 to 1 match, you get 10.000 results, Innerjoin will only return 100 rows in the same situation.
These 2 examples will return the same result:
Cross join
select * from table1 cross join table2 where table1.id = ...
In MySQL, can I copy one row to insert into the same table?
I just want to copy one row to insert into the same table (i.e., I want to duplicate an existing row in the table) but I want to do this without having to list all the columns after the "select", because this table has too many columns.
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Find the number of columns in a table
It is possible to find the number of rows in a table:
19 Answers
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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 ...