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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
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A cross join produces a cartesian product between the two tables, returning all possible combinations of all rows. It has no on clause because you're just joining everything to everything.
A full outer join is a combination of a left outer and right outer join. It returns all row...
Duplicating a MySQL table, indices, and data
...o I copy or clone or duplicate the data, structure,
and indices of a MySQL table to a new one?
10 Answers
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Error 1022 - Can't write; duplicate key in table
I'm getting a 1022 error regarding duplicate keys on create table command. Having looked at the query, I can't understand where the duplication is taking place. Can anyone else see it?
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Select first row in each GROUP BY group?
...also supports window functions (the CTE needs to be converted to a derived table though). And Firebird 3.0 will also support Window functions
– a_horse_with_no_name
Mar 14 '14 at 9:19
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How to detect that animation has ended on UITableView beginUpdates/endUpdates?
I am inserting/deleting table cell using insertRowsAtIndexPaths/deleteRowsAtIndexPaths wrapped in beginUpdates/endUpdates . I am also using beginUpdates/endUpdates when adjusting rowHeight. All these operations are animated by default.
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Oracle SQL: Update a table with data from another table
Table 1:
7 Answers
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How do I list the symbols in a .so file
...objdump -TC libz.so
libz.so: file format elf64-x86-64
DYNAMIC SYMBOL TABLE:
0000000000002010 l d .init 0000000000000000 .init
0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 free
0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 __errno_location
0000...
In MySQL, how to copy the content of one table to another table within the same database?
I am new to MySQL. I would like to copy the content of one table to another table within the same database. Basically, I would like to insert to a table from another table. Is there easy way of doing this?
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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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Hidden Features of MySQL
...t connections, but self compiled binaries often have less of a limit.
Set table_cache to match the number of your open tables and concurrent connections. Watch the open_tables value and if it is growing quickly you will need to increase its size.
Note:
The 2 previous parameters may require a lot...