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How do I expire a PHP session after 30 minutes?
...>
<html>
<form name="form1" method="post">
<table>
<tr>
<td>Username</td>
<td><input type="text" name="text"></td>
</tr>
<tr>
<td&g...
How can I insert values into a table, using a subquery with more than one result?
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If you are inserting one record into your table, you can do
INSERT INTO yourTable
VALUES(value1, value2)
But since you want to insert more than one record, you can use a SELECT FROM in your SQL statement.
so you will want to do this:
INSERT INTO prices (group,...
Summarizing multiple columns with dplyr? [duplicate]
... 2.87
#> 3 3 2.85 2.95 2.95 3.06
Also don't forget about data.table (use keyby to sort sort groups):
library(data.table)
setDT(df)[, lapply(.SD, mean), keyby = grp]
#> grp a b c d
#> 1: 1 3.079412 2.979412 2.979412 2.914706
#> 2: 2 3.029126 3....
Why does MYSQL higher LIMIT offset slow the query down?
Scenario in short: A table with more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
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How to remove not null constraint in sql server using query
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ALTER TABLE YourTable ALTER COLUMN YourColumn columnType NULL
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What are the applications of binary trees?
...nary Tries - Used in almost every high-bandwidth router for storing router-tables.
Hash Trees - used in p2p programs and specialized image-signatures in which a hash needs to be verified, but the whole file is not available.
Heaps - Used in implementing efficient priority-queues, which in turn are u...
In a storyboard, how do I make a custom cell for use with multiple controllers?
...he goal is to have those be re-usable throughout the app (ie, in any of my tableview controllers).
6 Answers
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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 {...
Conversion failed when converting date and/or time from character string while inserting datetime
I was trying to create a table as follows,
15 Answers
15
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Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...itectural register operands onto physical registers. Presumably it needs a table of uop-code -> dependency pattern and port choices, and grouping all uops for the same execution unit together simplifies that table. That's what I meant in more detail.
– Peter Cordes
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