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SQL JOIN - WHERE clause vs. ON clause
...
They are not the same thing.
Consider these queries:
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 12345
The first will re...
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...
Problem with converting int to string in Linq to entities
...ode ends up looking like this:
var items = from c in contacts
select new ListItem
{
Value = SqlFunctions.StringConvert((double)c.ContactId).Trim(),
Text = c.Name
};
...
Remove border radius from Select tag in bootstrap 3
...s gone, you have to add back in the arrow that visually differentiates the select from the input. Note: appearance is not supported in IE.
Working example: https://jsfiddle.net/gs2q1c7p/
select:not([multiple]) {
-webkit-appearance: none;
-moz-appearance: none;
background-positio...
How do I compare two files using Eclipse? Is there any option provided by Eclipse?
...
To compare two files in Eclipse, first select them in the Project Explorer / Package Explorer / Navigator with control-click. Now right-click on one of the files, and the following context menu will appear. Select Compare With / Each Other.
...
Regexp Java for password validation
...per case letter must occur at least once
(?=.*[@#$%^&+=]) # a special character must occur at least once
(?=\S+$) # no whitespace allowed in the entire string
.{8,} # anything, at least eight places though
$ # end-of-string
It's easy to add, modify or remo...
Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
Find the number of columns in a table
...
SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_catalog = 'database_name' -- the database
AND table_name = 'table_name'
share
...
What is the difference between UTF-8 and Unicode?
...r wants to use. Also, when a text editor program reads a file, it needs to select a text encoding scheme to decode it correctly. Same goes when you are typing and entering a letter, the text editor needs to know what scheme you use so that it will save it correctly.
– Cheng
...
Removing App ID from Developer Connection
...ifiers > App IDs"
Find the app id you wish to delete, highlight it and select "Settings". At the bottom of the resulting screen there is a "Delete" button.
Previously the only way to do this was to use a Safari & Chrome extension written by Simon Whitaker
app-id-sanity downloads
It giv...