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How to dismiss ViewController in Swift?
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answered Jul 10 '14 at 5:41
Zoon NoozZoon Nooz
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Transaction isolation levels relation with locks on table
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159
I want to understand the lock each transaction isolation takes on the table
For example, y...
How to shrink/purge ibdata1 file in MySQL
...ccording to Bill Karwin's comment this is enabled by default as of version 5.6.6 of MySQL.
It was a while ago I did this. However, to setup your server to use separate files for each table you need to change my.cnf in order to enable this:
[mysqld]
innodb_file_per_table=1
http://dev.mysql.com/do...
How to create an object for a Django model with a many to many field?
...fetch the two Bars, we save two SELECT statements, resulting in a total of 5:
INSERT INTO "app_foo" ("name") VALUES ()
SELECT "app_foo_bars"."id", "app_foo_bars"."foo_id", "app_foo_bars"."bar_id" FROM "app_foo_bars" WHERE "app_foo_bars"."foo_id" = 1
SELECT "app_foo_bars"."bar_id" FROM "app_foo_bars...
What does the thread_local mean in C++11?
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155
Thread-local storage duration is a term used to refer to data that is seemingly global or stati...
What is the maximum amount of RAM an app can use?
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answered Sep 7 '13 at 16:55
CommonsWareCommonsWare
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How to use custom packages
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edited Jan 18 '17 at 0:15
Edson Medina
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answere...
What does .SD stand for in data.table in R
...=c(1,3), v=1:6)
setkey(DT, y)
DT
# x y v
# 1: a 1 1
# 2: b 1 3
# 3: c 1 5
# 4: a 3 2
# 5: b 3 4
# 6: c 3 6
Doing this may help you see what .SD is:
DT[ , .SD[ , paste(x, v, sep="", collapse="_")], by=y]
# y V1
# 1: 1 a1_b3_c5
# 2: 3 a2_b4_c6
Basically, the by=y statement breaks the ...
JPA: How to have one-to-many relation of the same Entity type
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herau
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answered Aug 3 '10 at 4:54
Dan LaRocqueDan LaRocque
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