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How do I obtain a Query Execution Plan in SQL Server?
...mat.
Notes:
Because there are so many factors involved (ranging from the table and index schema down to the data stored and the table statistics) you should always try to obtain an execution plan from the database you are interested in (normally the one that is experiencing a performance problem)....
How are echo and print different in PHP? [duplicate]
...
$b ? print "true" : print "false";
print is also part of the precedence table which it needs to be if it
is to be used within a complex expression. It is just about at the bottom
of the precedence list though. Only , AND OR XOR are lower.
Parameter(s). The grammar is: echo expression [, expr...
Is there an auto increment in sqlite?
I am trying to create a table with an auto-incrementing primary key in Sqlite3 . I am not sure if this is really possible, but I am hoping to only have to designate the other fields.
...
Setting the MySQL root user password on OS X
... server in safe mode with privilege bypass
sudo mysqld_safe --skip-grant-tables;
In a new window connect to the database, set a new password and flush the permissions & quit:
mysql -u root
For MySQL older than MySQL 5.7 use:
UPDATE mysql.user SET Password=PASSWORD('your-password') WHERE ...
When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
... Or that memory just has been freed by HeapFree().
Disclaimer: the table is from some notes I have lying around - they may not be 100% correct (or coherent).
Many of these values are defined in vc/crt/src/dbgheap.c:
/*
* The following values are non-zero, constant, odd, large, and atypica...
MySQL order by before group by
...hor is to use a subquery to return the max date and then join that to your table on both the post_author and the max date.
The solution should be:
SELECT p1.*
FROM wp_posts p1
INNER JOIN
(
SELECT max(post_date) MaxPostDate, post_author
FROM wp_posts
WHERE post_status='publish'
...
Ruby on Rails: how do I sort with two columns using ActiveRecord?
...s, you should use the following more robust version: :order => ["DATE(#{table_name}.updated_at)", :price] (Note that :price is a symbol.)
– Jo Liss
Jul 31 '12 at 17:32
...
Delete sql rows where IDs do not have a match from another table
I'm trying to delete orphan entries in a mysql table.
3 Answers
3
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SQL Update with row_number()
... attempt failed primarily because you named the CTE same as the underlying table and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator.
Instead, you could just...
Change Default Scrolling Behavior of UITableView Section Header
I have a UITableView with two sections. It is a simple table view. I am using viewForHeaderInSection to create custom views for these headers. So far, so good.
...