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querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
I would like to know what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
...
Is having an 'OR' in an INNER JOIN condition a bad idea?
... a MERGE JOIN.
It can be expressed as a concatenation of two resultsets:
SELECT *
FROM maintable m
JOIN othertable o
ON o.parentId = m.id
UNION
SELECT *
FROM maintable m
JOIN othertable o
ON o.id = m.parentId
, each of them being an equijoin, however, SQL Server's optimiz...
Should you choose the MONEY or DECIMAL(x,y) datatypes in SQL Server?
...@num2 DECIMAL(19,4),
@num3 DECIMAL(19,4),
@num4 DECIMAL(19,4)
SELECT
@mon1 = 100, @mon2 = 339, @mon3 = 10000,
@num1 = 100, @num2 = 339, @num3 = 10000
SET @mon4 = @mon1/@mon2*@mon3
SET @num4 = @num1/@num2*@num3
SELECT @mon4 AS moneyresult,
@num4 AS numericresult...
using facebook sdk in Android studio
... what you want).
Open project structure by Ctrl + Shift + Alt + S and then select dependencies tab. Click on + button and select Module Dependency. In the new window pop up select :facebook.
You should be good to go.
Instructions for older Android Studio and older Facebook SDK
This applies to A...
Join between tables in two different databases?
...
Yes, assuming the account has appropriate permissions you can use:
SELECT <...>
FROM A.table1 t1 JOIN B.table2 t2 ON t2.column2 = t1.column1;
You just need to prefix the table reference with the name of the database it resides in.
...
- how to allow only one item selected?
I have a <SELECT multiple> field with multiple options and I want to allow it to have only one option selected at the same time but user can hold CTRL key and select more items at once.
...
How can you represent inheritance in a database?
...is is how you would have to query all the policies regardless of the type:
SELECT date_issued, other_common_fields, 'MOTOR' AS type
FROM policies_motor
UNION ALL
SELECT date_issued, other_common_fields, 'PROPERTY' AS type
FROM policies_property;
Note how adding new subtypes woul...
Which SQL query is faster? Filter on Join criteria or Where clause?
...INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = a.ID
AND a.ID = 1
LEFT JOIN
TableB b
ON x.TableBID = b.ID
or this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x...
Inefficient jQuery usage warnings in PHPStorm IDE
...o find a solution thanks to Scott Kosman here.
Basically the answer is to select IDs individually and then use .find(...) for anything below. So taking your example:
$("#property [data-role='content'] .container");
Changing it to this makes PhpStorm happy and can evidently be more than twice as ...
Create a date from day month and year with T-SQL
...are @Year Integer Set @Year = 2006
-- ------------------------------------
Select DateAdd(day, @DayOfMonth - 1,
DateAdd(month, @Month - 1,
DateAdd(Year, @Year-1900, 0)))
It works as well, has added benefit of not doing any string conversions, so it's pure arithmetic proce...