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How to check if field is null or empty in MySQL?
...
Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
...
LEFT OUTER JOIN in LINQ
...c.Category equals p.Category into ps
from p in ps.DefaultIfEmpty()
select new { Category = c, ProductName = p == null ? "(No products)" : p.ProductName };
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How to create a dialog with “yes” and “no” options?
... dynamically-generated elements:
a and button clicks
form submits
option selects
jQuery:
$(document).on('click', ':not(form)[data-confirm]', function(e){
if(!confirm($(this).data('confirm'))){
e.stopImmediatePropagation();
e.preventDefault();
}
});
$(document).on('submi...
How do I assign an alias to a function name in C++?
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typedef int (*printf_alias)(const char*, ...);
printf_alias holler = std::printf;
Should do you fine.
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EF LINQ include multiple and nested entities
...de:
Course course = db.Courses
.Include(i => i.Modules.Select(s => s.Chapters))
.Include(i => i.Lab)
.Single(x => x.Id == id);
Your solution fails because Include doesn't take a boolean operator
Include(i => i.Modules.Select(s => ...
Order a MySQL table by two columns
...h query not working in my case.. Tn this case, I dont get sorting for City select distinct City, Country from customers order by Country desc, City desc;
– Pra_A
Sep 15 '16 at 6:55
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How do I import .sql files into SQLite 3?
...d - you need ; on the end of your statements:
create table server(name varchar(50),ipaddress varchar(15),id init);
create table client(name varchar(50),ipaddress varchar(15),id init);
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How to replace strings containing slashes with sed?
... search/replace lines, e.g.:
s:?page=one&:pageone:g
You can use any character as a delimiter that's not part of either string. Or, you could escape it with a backslash:
s/\//foo/
Which would replace / with foo. You'd want to use the escaped backslash in cases where you don't know what char...
Convert timestamp to date in MySQL query
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SELECT * FROM users WHERE DATE_FORMAT(FROM_UNIXTIME(users.user_created_at),'%Y-%b-%e') = '2015-03-06' is this correct format or should i modify this?
– Dheeraj Thedijje
Mar 7 '18 at 11:4...
Remove all classes that begin with a certain string
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Careful with this one. Word boundary splits on dash character ('-') and dots and others, so class names like "bg.a", "bg-a" etc. will not be removed but replaced with ".a", "-a" etc. So if you have classnames with punctuation characters you may run into trouble by just running...