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Difference between a theta join, equijoin and natural join
...uijoin will also remove the equality column if they have same name in both tables.
– Vishal R
Nov 13 '14 at 3:42
1
...
Remove all spaces from a string in SQL Server
... trim() or worry about multiple spaces for either char or varchar:
create table #t (
c char(8),
v varchar(8))
insert #t (c, v) values
('a a' , 'a a' ),
('a a ' , 'a a ' ),
(' a a' , ' a a' ),
(' a a ', ' a a ')
select
'"' + c + '"' [IN], '"' + replac...
How to select the last record of a table in SQL?
This is a sample code to select all records from a table. Can someone show me how to select the last record of that table?
...
Is SHA-1 secure for password storage?
...ht now even with the "broken" hash functions MD5 and SHA-1.
About rainbow tables:
The "rainbow attack" is actually cost-sharing of a dictionary or brute force attack. It is a derivative from the time-memory trade-off first described by Hellman in 1980. Assuming that you have N possible passwords (...
MySQL Query GROUP BY day / month / year
... Simple complete example: SELECT count(*), record_date FROM anytable WHERE anytable.anycolumn = 'anycondition' GROUP BY YEAR(record_date), month(record_date); note: record_date is a date type TIMESTAMP
– renedet
Jul 25 '17 at 18:35
...
CSS Cell Margin
In my HTML document, I have a table with two columns and multiple rows. How can I increase the space in between the first and second column with css? I've tried applying "margin-right: 10px;" to each of the cells on the left hand side, but to no effect.
...
PHP code to convert a MySQL query to CSV [closed]
...MINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $select ) or die ( "Sql error : " . mysql_error( ) );
$fi...
When to use MyISAM and InnoDB? [duplicate]
...s better for beginners. No worries about the foreign relationships between tables.
Faster than InnoDB on the whole as a result of the simpler structure thus much less costs of server resources. -- Mostly no longer true.
Full-text indexing. -- InnoDB has it now
Especially good for read-intensive (se...
MySQL ON DUPLICATE KEY - last insert id?
...on to that MySQL function.
From the MySQL documentation example:
If a table contains an AUTO_INCREMENT column and INSERT ... UPDATE inserts a row, the LAST_INSERT_ID() function returns the AUTO_INCREMENT value. If the statement updates a row instead, LAST_INSERT_ID() is not meaningful. However,...
How do I drop a foreign key in SQL Server?
...
Try
alter table company drop constraint Company_CountryID_FK
alter table company drop column CountryID
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