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The object cannot be deleted because it was not found in the ObjectStateManager
... var project = context.Projects
.Include(p => p.Reports.Select(q => q.Issues.Select(r => r.Profession)))
.Include(p => p.Reports.Select(q => q.Issues.Select(r => r.Room)))
.SingleOrDefault(x => x.Id == id);
return proje...
How do I get SUM function in MySQL to return '0' if no values are found?
...
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
How can I pad a value with leading zeros?
...ad+n).slice(-pad.length);
As a function,
function paddy(num, padlen, padchar) {
var pad_char = typeof padchar !== 'undefined' ? padchar : '0';
var pad = new Array(1 + padlen).join(pad_char);
return (pad + num).slice(-pad.length);
}
var fu = paddy(14, 5); // 00014
var bar = paddy(2, 4,...
Add primary key to existing table
...PMID)
edit:
you can find the constraint name by using the query below:
select OBJECT_NAME(OBJECT_ID) AS NameofConstraint
FROM sys.objects
where OBJECT_NAME(parent_object_id)='Persion'
and type_desc LIKE '%CONSTRAINT'
sh...
How to set selected value on select using selectpicker plugin from bootstrap
I'm using the Bootstrap-Select plugin like this:
18 Answers
18
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COUNT DISTINCT with CONDITIONS
...
You can try this:
select
count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex...
SQL Server - Create a copy of a database table and place it in the same database?
...
Use SELECT ... INTO:
SELECT *
INTO ABC_1
FROM ABC;
This will create a new table ABC_1 that has the same column structure as ABC and contains the same data. Constraints (e.g. keys, default values), however, are -not- copied.
...
Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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On delete cascade with doctrine2
...REATE TABLE contacts
(contact_id BIGINT AUTO_INCREMENT NOT NULL,
name VARCHAR(75) NOT NULL,
PRIMARY KEY(contact_id)) ENGINE = InnoDB;
CREATE TABLE phone_numbers
(phone_id BIGINT AUTO_INCREMENT NOT NULL,
phone_number CHAR(10) NOT NULL,
contact_id BIGINT NOT NULL,
PRIMARY KEY(phone_id),
UNIQ...
Efficient way to return a std::vector in c++
...
vector<string> getseq(char * db_file)
And if you want to print it on main() you should do it in a loop.
int main() {
vector<string> str_vec = getseq(argv[1]);
for(vector<string>::iterator it = str_vec.begin(); it != str_ve...