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MySQL check if a table exists without throwing an exception
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If you're using MySQL 5.0 and later, you could try:
SELECT COUNT(*)
FROM information_schema.tables
WHERE table_schema = '[database name]'
AND table_name = '[table name]';
Any results indicate the table exists.
From: http://www.electrictoolbox.com/check-if-mysql-table-exis...
Which kind of pointer do I use when?
...covariant return and non-owning. A rewrite might be good if you meant the union rather than intersection. I'd also say that iteration is worth special mention also.
– Ben Voigt
Jan 2 '12 at 23:11
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C# equivalent to Java's charAt()?
I know we can use the charAt() method in Java get an individual character in a string by specifying its position. Is there an equivalent method in C#?
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How do you change the server header returned by nginx?
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## vi src/http/ngx_http_header_filter_module.c (lines 48 and 49)
static char ngx_http_server_string[] = "Server: MyDomain.com" CRLF;
static char ngx_http_server_full_string[] = "Server: MyDomain.com" CRLF;
March 2011 edit: Props to Flavius below for pointing out a new option, replacing Nginx's ...
fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'X86'
...t; Configuration Properties > Linker > Advanced > Target Machine. Select MachineX64 if you are targeting a 64 bit build, or MachineX86 if you are making a 32 bit build.
Select Build > Configuration Manager from the main menu in visual studio. Make sure your project has the correct platfo...
How does the algorithm to color the song list in iTunes 11 work? [closed]
...hold &];
If[filterColor =!= 0,
buckets =
Select[buckets,
ColorDistance[ Mean[#1], filterColor] > filterThreshold &]];
buckets = Sort[buckets, Length[#1] > Length[#2] &];
If[Length @ buckets == 0, Return[{}]];
co...
What is the memory consumption of an object in Java?
... storage overhead.
String: a String's memory growth tracks its internal char array's growth. However, the String class adds another 24 bytes of overhead.
For a nonempty String of size 10 characters or less, the added overhead cost relative to useful payload (2 bytes for each char plus 4 byte...
pandas dataframe columns scaling with sklearn
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@RajeshThevar The outer brackets are pandas' typical selector brackets, telling pandas to select a column from the dataframe. The inner brackets indicate a list. You're passing a list to the pandas selector. If you just use single brackets - with one column name followed by ...
Is 23,148,855,308,184,500 a magic number, or sheer chance?
...eth Lewis in Owatonna .
The thing is that all of them have the exact same charge: $23,148,855,308,184,500.00. If the problem was the space-padding, then how is it that all of them had the exact same $0x1250 ($46.88) charge? Two of them had purchased cigarettes at gas stations, another two had paid ...
How to replace a character by a newline in Vim
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Use \r instead of \n.
Substituting by \n inserts a null character into the text. To get a newline, use \r. When searching for a newline, you’d still use \n, however. This asymmetry is due to the fact that \n and \r do slightly different things:
\n matches an end of line (newline...