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How can I append a string to an existing field in MySQL?
I want to update the code on all my record to what they currently are plus _standard any ideas?
2 Answers
...
Array versus List: When to use which?
...he underlying stream (and v.v.); quicker than BufferedStream etc;
it internally uses an array-based model of objects (Foo[] rather than List<Foo>), since the size is fixed once built, and needs to be very fast.
But this is definitely an exception; for general line-of-business processing, a L...
SSH to Elastic Beanstalk instance
...ty group to add a rule for SSH access. The below will lock it down to only allow ingress from a specific IP address.
SSH | tcp | 22 | 22 | 192.168.1.1/32
Configure the environment of your Elastic Beanstalk Application
If you haven't made a key pair yet, make one by clicking Key Pairs below Sec...
Clojure differences between Ref, Var, Agent, Atom, with examples
... one bank account to another, it needs to either move completely or not at all.
Uncoordinated access is used when only one Identity needs to update, this is a very common case.
Synchronous access is used when the call is expected to wait until all Identities have settled before continuing.
Asy...
Split string on the first white space occurrence
...tr.indexOf(' ')+1); // "tocirah sneab"
Note that if there is no space at all, then the first line will return an empty string and the second line will return the entire string. Be sure that is the behavior that you want in that situation (or that that situation will not arise).
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cartesian product in pandas
...n unused column name, then add dummy columns with that name, merge, and finally drop the column on the result? Creating, as opposed to reading, data with pandas is just a pain
– Bananach
Oct 10 '19 at 7:31
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Modifying location.hash without page scrolling
...reated and placed at the current location of the scroll. It's the same visually as position:fixed/top:0. Thus the scrollbar is "moved" to the exact same spot it currently is on.
– Borgar
Sep 29 '09 at 0:44
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e.printStackTrace equivalent in python
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import traceback
traceback.print_exc()
When doing this inside an except ...: block it will automatically use the current exception. See http://docs.python.org/library/traceback.html for more information.
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How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
C++实现一款简单完整的聊天室服务器+客户端 - C/C++ - 清泛网 - 专注C/C++及内核技术
...从缓冲区中取出消息
MessageBuffer.h
//MessageBuffer.h
#ifndef _MESSAGE_BUF_INCLUDE_
#define _MESSAGE_BUF_INCLUDE_
#include <pthread.h>
#define MESSAGE_COUNT 16
#define MESSAGE_LENGTH 2048
class MessageBuffer{
private:
pthread_mutex_t mutex;//访问缓冲的互斥量
pthread_...