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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 = ...
Remove duplicate rows in MySQL
I have a table with the following fields:
25 Answers
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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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Return number of rows affected by UPDATE statements
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CREATE PROCEDURE UpdateTables
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @RowCount1 INTEGER
DECLARE @RowCount2 INTEGER
DECLARE @RowCount3...
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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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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PostgreSQL: Show tables in PostgreSQL
What's the equivalent to show tables (from MySQL) in PostgreSQL?
24 Answers
24
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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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List of foreign keys and the tables they reference
...ying to find a query which will return me a list of the foreign keys for a table and the tables and columns they reference. I am half way there with
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How can I list all foreign keys referencing a given table in SQL Server?
I need to remove a highly referenced table in a SQL Server database. How can I get a list of all the foreign key constraints I will need to remove in order to drop the table?
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