大约有 40,000 项符合查询结果（耗时：0.0346秒） [XML]
Is there any performance gain in indexing a boolean field?
...
It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
IntelliJ: Working on multiple projects
...ven Projects" window (View > Tool Windows > Maven Projects) and then select the additional pom file you want to import.
share
|
improve this answer
|
follow
...
MySQL Insert Where query
...INSERT INTO Users(weight, desiredWeight)
VALUES (160,145)
INSERT using a SELECT statement
INSERT INTO Users(weight, desiredWeight)
SELECT weight, desiredWeight
FROM AnotherTable
WHERE id = 1
share
|
...
Unable to export Apple production push SSL certificate in .p12 format
...
Turns out all you have to do is select "My Certificates" on the left panel and it enables the .p12 option.
share
|
improve this answer
|
...
How to use jQuery to select a dropdown option?
I was wondering if it’s possible to get jQuery to select an <option> , say the 4th item, in a dropdown box?
13 Ans...
Filter element based on .data() key/value
...class .navlink , which, when clicked, use .data() to set a key called 'selected' , to a value of true :
5 Answers
...
Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
...
Accessing an SQLite Database in Swift
...pared statement: \(errmsg)")
}
statement = nil
Prepare new statement for selecting values from table and loop through retrieving the values:
if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
pri...
How to trim a string in SQL Server before 2017?
...
SELECT LTRIM(RTRIM(Names)) AS Names FROM Customer
share
|
improve this answer
|
follow
...
The entity cannot be constructed in a LINQ to Entities query
... p in db.Products
where p.CategoryID == categoryID
select new ProductDTO { Name = p.Name }).ToList();
}
share
|
improve this answer
|
follow
...