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How to delete from select in MySQL?
... clause.
Additionally, as shown in this answer you cannot modify the same table from a subquery within the same query. However, you can either SELECT then DELETE in separate queries, or nest another subquery and alias the inner subquery result (looks rather hacky, though):
DELETE FROM posts WHERE ...
MySQL pagination without double-querying?
... this tickles that affects ORDER BY queries making it much slower on large tables than the naive approach of two queries.
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Only one expression can be specified in the select list when the subquery is not introduced with EXI
...r side of the IN. So the query needs to be of the form:
SELECT * From ThisTable WHERE ThisColumn IN (SELECT ThatColumn FROM ThatTable)
You also want to add sorting so you can select just from the top rows, but you don't need to return the COUNT as a column in order to do your sort; sorting in the...
SQL multiple column ordering
... @NickBenes ...or you could say: it sorts by column2 and then performs STABLE sorting by column1. This is more clear for people that knows what stable sorting is.
– Atom
Oct 3 '16 at 13:49
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PostgreSQL: How to make “case-insensitive” query
...indexes to no longer be seekable. If this is a large or frequently queried table, that could cause trouble. Case-insensitive collation, citext, or a function-based index will improve performance.
– Jordan
Aug 10 '11 at 4:23
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LINQ Join with Multiple Conditions in On Clause
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This works fine for 2 tables. I have 3 tables and on clause has to link 2 conditions from 3 tables.
My code:
from p in _dbContext.Products
join pv in _dbContext.ProductVariants on p.ProduktId equals pv.ProduktId
join jpr in leftJoinQuery
on new {...
ng-repeat finish event
I want to call some jQuery function targeting div with table. That table is populated with ng-repeat .
15 Answers
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Why are ToLookup and GroupBy different?
...happens when you call ToLookup on an object representing a remote database table with a billion rows in it?
The billion rows are sent over the wire, and you build the lookup table locally.
What happens when you call GroupBy on such an object?
A query object is built; end of story.
When that quer...
How should you build your database from source control?
...sing automation - or should production by built by copying objects from a stable, finalized test environment?
Automation for both. Do NOT copy data between the environments
How do you deal with potential differences between test and production environments in deployment scripts?
Use templates, so th...
Binary Data in MySQL [closed]
...
For a table like this:
CREATE TABLE binary_data (
id INT(4) NOT NULL AUTO_INCREMENT PRIMARY KEY,
description CHAR(50),
bin_data LONGBLOB,
filename CHAR(50),
filesize CHAR(50),
filetype CHAR(50)
);
Here is...