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Is storing a delimited list in a database column really that bad?
...ient table-scan. May have to resort to regular expressions, for example in MySQL:
idlist REGEXP '[[:<:]]2[[:>:]]'*
Hard to count elements in the list, or do other aggregate queries.
Hard to join the values to the lookup table they reference.
Hard to fetch the list in sorted order.
To solve th...
How to switch databases in psql?
In MySQL , I used use database_name;
12 Answers
12
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SQL Server - inner join when updating [duplicate]
...it works with UDPATE SET FROM JOIN WHERE? Does it depend on the version of mysql?
– Farside
Apr 28 '16 at 12:45
6
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Deploying my application at the root in Tomcat
I have the war file of my application. I need to deploy this at the root level. The current URL is http://localhost:8080/war_name/application_name .
...
How to get root access on Android emulator?
...roid SDK versions(from 1.5 to 2.3.3), and I tried many methods for getting root in Android emulator. I don't use any Android device and test everything on emulator(AVD).
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What is sharding and why is it important?
...cross multiple logical or physical nodes (in the case of my understanding (mySQL) multiple databases, most likely housed on different logical hardware). Horizontal partitioning is a less specific term, of which "Sharding" is a subset. Again using mySQL as an example, a mySQL partition is handled by...
Is bool a native C type?
...goto
if
int
long
register
return
short
signed
static
struct
switch
typedef
union
unsigned
void
volatile
while
Here's an article discussing some other differences with C as used in the kernel and the standard: http://www.ibm.com/developerworks/linux/library/l-gcc-hacks/index.html
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App Inventor 2 低功耗蓝牙 BlueToothLE 拓展 · App Inventor 2 中文网
... Disconnect 或 DisconnectWithAddress 引起的,或者在设备移开或重置以致发生连接丢失后引起的。
FloatsReceived – 当从连接的蓝牙设备接收到一个或多个 IEEE 754 浮点值时,将触发该事件。根据上次调用 ReadFloats 或 RegisterForFlo...
Count the occurrences of DISTINCT values
I am trying to find a MySQL query that will find DISTINCT values in a particular field, count the number of occurrences of that value and then order the results by the count.
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When NOT to use Cassandra?
...ase of RDBMS, making a choice is quite easy because all the databases like MySQL, Oracle, MS SQL, PostgreSQL in this category offer almost the same kind of solutions oriented toward ACID properties. When it comes to NoSQL, the decision becomes difficult because every NoSQL database offers different ...
