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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 = ...
MySQL Cannot drop index needed in a foreign key constraint
...e foreign key. Foreign keys in MySQL automatically create an index on the table (There was a SO Question on the topic).
ALTER TABLE mytable DROP FOREIGN KEY mytable_ibfk_1 ;
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List all tables in postgresql information_schema
What is the best way to list all of the tables within PostgreSQL's information_schema?
8 Answers
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Remove duplicate rows in MySQL
I have a table with the following fields:
25 Answers
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Can I use a min-height for table, tr or td?
I am trying to show some details of a receive in a table.
7 Answers
7
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Query to list number of records in each table in a database
How to list row count of each table in the database. Some equivalent of
21 Answers
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Colspan all columns
... td tag should span all columns (when the exact amount of columns in the table will be variable/difficult to determine when the HTML is being rendered)? w3schools mentions you can use colspan="0" , but it doesn't say exactly what browsers support that value (IE 6 is in our list to support).
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What is a 'multi-part identifier' and why can't it be bound?
I continually get these errors when I try to update tables based on another table. I end up rewriting the query, change the order of joins, change some groupings and then it eventually works, but I just don't quite get it.
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PostgreSQL: Show tables in PostgreSQL
What's the equivalent to show tables (from MySQL) in PostgreSQL?
24 Answers
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Tools for making latex tables in R [closed]
On general request, a community wiki on producing latex tables in R. In this post I'll give an overview of the most commonly used packages and blogs with code for producing latex tables from less straight-forward objects. Please feel free to add any I missed, and/or give tips, hints and little trick...