大约有 47,000 项符合查询结果(耗时:0.0250秒) [XML]
What are the most common SQL anti-patterns? [closed]
...ost programmers' tendency to mix their UI-logic in the data access layer:
SELECT
FirstName + ' ' + LastName as "Full Name",
case UserRole
when 2 then "Admin"
when 1 then "Moderator"
else "User"
end as "User's Role",
case SignedIn
when 0 then "Logged i...
How do I get the size of a java.sql.ResultSet?
...
Do a SELECT COUNT(*) FROM ... query instead.
OR
int size =0;
if (rs != null)
{
rs.last(); // moves cursor to the last row
size = rs.getRow(); // get row id
}
In either of the case, you won't have to loop over the enti...
How do you use variables in a simple PostgreSQL script?
...c/sql-do.html )
DO $$
DECLARE v_List TEXT;
BEGIN
v_List := 'foobar' ;
SELECT *
FROM dbo.PubLists
WHERE Name = v_List;
-- ...
END $$;
Also you can get the last insert id:
DO $$
DECLARE lastid bigint;
BEGIN
INSERT INTO test (name) VALUES ('Test Name')
RETURNING id INTO lastid;
...
MySQL case insensitive select
Can anyone tell me if a MySQL SELECT query is case sensitive or case insensitive by default? And if not, what query would I have to send so that I can do something like:
...
View's SELECT contains a subquery in the FROM clause
...
As per documentation:
MySQL Docs
The SELECT statement cannot contain a subquery in the FROM clause.
Your workaround would be to create a view for each of your subqueries.
Then access those views from within your view view_credit_status
...
Difference between natural join and inner join
...+----------+
The INNER JOIN of TableA and TableB on Column1 will return
SELECT * FROM TableA AS a INNER JOIN TableB AS b USING (Column1);
SELECT * FROM TableA AS a INNER JOIN TableB AS b ON a.Column1 = b.Column1;
+------------+-----------+---------------------+
| a.Column1 | a.Column2 | ...
-didSelectRowAtIndexPath: not being called
...de a tab view. In my UITableViewController , I implemented -tableView:didSelectRowAtIndexPath: , but when I select a row at runtime, the method isn't being called. The table view is being populated though, so I know that other tableView methods in my controller are being called.
...
Making a WinForms TextBox behave like your browser's address bar
...etty straightforward and seems to work in all the scenarios (mousing down, selecting text, tabbing focus, etc.)
bool alreadyFocused;
...
textBox1.GotFocus += textBox1_GotFocus;
textBox1.MouseUp += textBox1_MouseUp;
textBox1.Leave += textBox1_Leave;
...
void textBox1_Leave(object sender, EventAr...
how to schedule a job for sql query to run daily?
...QL Server Agent node and right click the Jobs node in SQL Server Agent and select 'New Job'
In the 'New Job' window enter the name of the job and a description on the 'General' tab.
Select 'Steps' on the left hand side of the window and click 'New' at the bottom.
In the 'Steps' window enter a step n...
“Large data” work flows using pandas
...ns?
What will typical operations look like. E.g. do a query on columns to select a bunch of rows and specific columns, then do an operation (in-memory), create new columns, save these.
(Giving a toy example could enable us to offer more specific recommendations.)
After that processing, then what do...
