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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 ...
updating table rows in postgres using subquery
Using postgres 8.4, My goal is to update existing table:
6 Answers
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Freeze the top row for an html table only (Fixed Table Header Scrolling) [duplicate]
I want to make an html table with the top row frozen (so when you scroll down vertically you can always see it).
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Why does overflow:hidden not work in a ?
I've got a table cell that I would always like to be a particular width. However, it doesn't work with large strings of unspaced text. Here's a test case:
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Multi-statement Table Valued Function vs Inline Table Valued Function
...He is correct, there will be a difference in performance between an inline table valued function (ITVF) and a multi-statement table valued function (MSTVF) even if they both simply execute a SELECT statement. SQL Server will treat an ITVF somewhat like a VIEW in that it will calculate an execution p...
MySQL Delete all rows from table and reset ID to zero
I need to delete all rows from a table but when I add a new row, I want the primary key ID, which has an auto increment, to start again from 0 respectively from 1.
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