大约有 40,000 项符合查询结果（耗时：0.0647秒） [XML]
Throw an error in a MySQL trigger
...e SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a more complete example of the approach:
delimiter //
use test//
create table trigger_test
(
id int...
Mercurial .hgignore for Visual Studio 2008 projects
...re Visual Studio 2008 files
*.obj
*.exe
*.pdb
*.user
*.aps
*.pch
*.vspscc
*_i.c
*_p.c
*.ncb
*.suo
*.tlb
*.tlh
*.bak
*.cache
*.ilk
*.log
*.lib
*.sbr
*.scc
[Bb]in
[Dd]ebug*/
obj/
[Rr]elease*/
_ReSharper*/
[Tt]est[Rr]esult*
[Bb]uild[Ll]og.*
*.[Pp]ublish.xml
...
Invert “if” statement to reduce nesting
... clearer. For example:
double getPayAmount() {
double result;
if (_isDead) result = deadAmount();
else {
if (_isSeparated) result = separatedAmount();
else {
if (_isRetired) result = retiredAmount();
else result = normalPayAmount();
};
...
Adding a new value to an existing ENUM Type
...he new type.
-- 1. rename the enum type you want to change
alter type some_enum_type rename to _some_enum_type;
-- 2. create new type
create type some_enum_type as enum ('old', 'values', 'and', 'new', 'ones');
-- 3. rename column(s) which uses our enum type
alter table some_table rename column some...
No mapping found for field in order to sort on in ElasticSearch
...
After digging more, I found the solution as given below. ignore_unmapped should be explicitly set to true in the sort clause.
"sort" : [
{ "rating": {"order" : "desc" , "ignore_unmapped" : true} },
{ "price": {"order" : "asc" , "missing" : "_last" , "ignore_unmapped" : tru...
Is Chrome's JavaScript console lazy about evaluating arrays?
...confirmed Webkit bug that explains this issue: https://bugs.webkit.org/show_bug.cgi?id=35801 (EDIT: now fixed!)
There appears to be some debate regarding just how much of a bug it is and whether it's fixable. It does seem like bad behavior to me. It was especially troubling to me because, in Chro...
Render basic HTML view?
...te.
Using express 3.0.0 and 3.1.0, the following works:
app.set('views', __dirname + '/views');
app.engine('html', require('ejs').renderFile);
See the comments below for alternative syntax and caveats for express 3.4+:
app.set('view engine', 'ejs');
Then you can do something like:
app.get('/...
Why is it string.join(list) instead of list.join(string)?
...ct, set), but the result and the "joiner" must be strings.
For example:
'_'.join(['welcome', 'to', 'stack', 'overflow'])
'_'.join(('welcome', 'to', 'stack', 'overflow'))
'welcome_to_stack_overflow'
Using something else than strings will raise the following error:
TypeError: sequence item 0...
How to get the full path of running process?
... wmiQueryString = "SELECT ProcessId, ExecutablePath, CommandLine FROM Win32_Process";
using (var searcher = new ManagementObjectSearcher(wmiQueryString))
using (var results = searcher.Get())
{
var query = from p in Process.GetProcesses()
join mo in results.Cast<ManagementObjec...
How can I search for a multiline pattern in a file?
... Regular Expressions GREP.
For example, you need to find files where the '_name' variable is immediatelly followed by the '_description' variable:
find . -iname '*.py' | xargs pcregrep -M '_name.*\n.*_description'
Tip: you need to include the line break character in your pattern. Depending on yo...