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MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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...
C/C++ with GCC: Statically add resource files to executable/library
... an iterator.
If you're using this with automake don't forget to set BUILT_SOURCES appropriately.
The nice thing about doing it this way is:
You get text out, so it can be in version control and patches sensibly
It is portable and well defined on every platform
...
Difference between passing array and array pointer into function in C
... eax, 0Fh
add eax, 0Fh
shr eax, 4
shl eax, 4
mov [ebp+var_C], eax
mov eax, [ebp+var_C]
call sub_401730
call sub_4013D0
mov [ebp+var_8], 2
mov [ebp+var_4], 4
lea eax, [ebp+var_8]
mov [esp+18h+var_18], eax
call sub_401290
call _getch
leave
retn
So th...
AfxGetMainWnd函数解惑 - C/C++ - 清泛网 - 专注C/C++及内核技术
...时也会失灵。不信， 你测试一下下面的代码：
unsigned __stdcall SecondThreadFunc( void* pArguments )
{
CMainFrame* pMainWnd = (CMainFrame*)AfxGetMainWnd();
if (NULL!=pMainWnd)
{
CView *pView = pMainWnd->GetActiveView();
if (NULL...
Discuz菜单栏下面广告怎么弄？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
... class="z dzfbr">
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<em class="xg2">自强·求变，跨界实践绿色增长</em>
<em><a href="http://www.discuz.net/thread-1591466-1-1.html" target="_blank">火...
CPU指令集avx程序无法运行，运行崩溃 - C/C++ - 清泛网 - 专注C/C++及内核技术
CPU指令集avx程序无法运行，运行崩溃cpu_avx_run原因就是CPU不支持相应的指令集导致的。Linux上使用 lscpu 命令查看CPU指令集，看是否支持。比如_mm256_cmpeq_epi64 这个函数需要avx2指令集，但是CPU不支持，就导致程序崩溃起不来。原因...
Debian/Linux下安装OpenJDK8 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
Debian/Linux下安装OpenJDK8linux_install_openjdk8因为Debian11的源里不再带OpenJDK8了，需要手工来安装。下载安装包因为手工安装，所以部分依赖包需要自己下载。wget http: snapshot debian org archive debian-security 202202 因为Debian11的源里不再带Open...
App Inventor 2 EV3超声波传感器教程 · App Inventor 2 中文网
...通过蓝牙连接EV3，读取各种传感器。
已有文档：bluetooth_remote.md 介绍了蓝牙通信。本文聚焦EV3超声波传感器。
EV3组件
添加组件
组件面板 → LEGO MINDSTORMS → **Ev3 Ultrasonic Sensor`
支持的...
_csv.Error: field larger than field limit (131072)
...
The csv file might contain very huge fields, therefore increase the field_size_limit:
import sys
import csv
csv.field_size_limit(sys.maxsize)
sys.maxsize works for Python 2.x and 3.x. sys.maxint would only work with Python 2.x (SO: what-is-sys-maxint-in-python-3)
Update
As Geoff pointed out,...
How to write very long string that conforms with PEP8 and prevent E501
....
from paragraphs import par
class SuddenDeathError(Exception):
def __init__(self, cause: str) -> None:
self.cause = cause
def __str__(self):
return par(
f""" Y - e - e - e - es, Lord love you! Why should she die of
{self.cause}? She come throug...