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What is the optimal length for an email address in a database?
...s though.
Again, since a varchar only uses the space actually used by the string you store, there is no reason to have a small limit for email address length. Just go with 512 and stop worrying. Everything else is premature optimization
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UUID max character length
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Section 3 of RFC4122 provides the formal definition of UUID string representations. It's 36 characters (32 hex digits + 4 dashes).
Sounds like you need to figure out where the invalid 60-char IDs are coming from and decide 1) if you want to accept them, and 2) what the max length of...
Is there a splice method for strings?
...he Javascript splice only works with arrays. Is there similar method for strings? Or should I create my own custom function?
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How do I read an entire file into a std::string in C++?
How do I read a file into a std::string , i.e., read the whole file at once?
15 Answers
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How to use GROUP BY to concatenate strings in SQL Server?
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A slightly cleaner way of doing the string manipulation: STUFF((SELECT ', ' + [Name] + ':' + CAST([Value] AS VARCHAR(MAX)) FROM #YourTable WHERE (ID = Results.ID) FOR XML PATH ('')),1,2,'') AS NameValues
– Jonathan Sayce
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Write to .txt file?
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FILE *fp;
char* str = "string";
int x = 10;
fp=fopen("test.txt", "w");
if(fp == NULL)
exit(-1);
fprintf(fp, "This is a string which is written to a file\n");
fprintf(fp, "The string has %d words and keyword %s\n", x, str);
fclose(fp);
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Capitalize first letter. MySQL
...= CONCAT(UCASE(LEFT(CompanyIndustry, 1)),
SUBSTRING(CompanyIndustry, 2));
This would turn hello to Hello, wOrLd to WOrLd, BLABLA to BLABLA, etc. If you want to upper-case the first letter and lower-case the other, you just have to use LCASE function :
UPDATE tb_Compa...
Test whether string is a valid integer
...aining it so I can learn a little? I gather it reads, "At the start of the string (^), a minus sign (-) is optional (?), followed by any number of characters between zero and 9, inclusive" ... and what then might the +$ mean? Thanks.
– Richard T
Feb 5 '10 at 21...
How to get the input from the Tkinter Text Widget?
...the very first character). END is an imported constant which is set to the string "end". The END part means to read until the end of the text box is reached. The only issue with this is that it actually adds a newline to our input. So, in order to fix it we should change END to end-1c(Thanks Bryan O...
C++11 tuple 这一篇就够了 - C/C++ - 清泛网 - 专注C/C++及内核技术
...的多个tuple）。
#include <iostream>
#include <utility>
#include <string>
#include <tuple>
int main ()
{
std::tuple<float,std::string> mytuple (3.14,"pi");
std::pair<int,char> mypair (10,'a');
auto myauto = std::tuple_cat ( mytuple, mypair );
std::cout << "myauto contai...