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MySQL Error 1093 - Can't specify target table for update in FROM clause
...s question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple enough to re-shape the query, lose the subquery and join th...
Fluent and Query Expression — Is there any benefit(s) of one over other?
...me in fullNames
from name in fullName.Split()
orderby fullName, name
select name + " came from " + fullName;
Now compare this to the same thing in method syntax:
var query = fullNames
.SelectMany (fName => fName.Split().Select (name => new { name, fName } ))
.OrderBy (x => x.fN...
Datatype for storing ip address in SQL Server
...VARCHAR(15)) RETURNS BINARY(4)
AS
BEGIN
DECLARE @bin AS BINARY(4)
SELECT @bin = CAST( CAST( PARSENAME( @ip, 4 ) AS INTEGER) AS BINARY(1))
+ CAST( CAST( PARSENAME( @ip, 3 ) AS INTEGER) AS BINARY(1))
+ CAST( CAST( PARSENAME( @ip, 2 ) AS INTEGER) AS BINARY(1))
...
Split function equivalent in T-SQL?
...AR(2048) = 'Mike/John/Miko/Matt'; DECLARE CaracString NVARCHAR(1) = '/'; SELECT * FROM dbo.FnSplitString (VarString, CaracString)
– fernando yevenes
Feb 8 '19 at 15:57
ad...
How to keep onItemSelected from firing off on a newly instantiated Spinner?
...
I would have expected your solution to work -- I though the selection event would not fire if you set the adapter before setting up the listener.
That being said, a simple boolean flag would allow you to detect the rogue first selection event and ignore it.
...
How do you create a read-only user in PostgreSQL?
I'd like to create a user in PostgreSQL that can only do SELECTs from a particular database. In MySQL the command would be:
...
Check if value exists in Postgres array
...
Simpler with the ANY construct:
SELECT value_variable = ANY ('{1,2,3}'::int[])
The right operand of ANY (between parentheses) can either be a set (result of a subquery, for instance) or an array. There are several ways to use it:
SQLAlchemy: how to filt...
How to select only the first rows for each unique value of a column
...
A very simple answer if you say you don't care which address is used.
SELECT
CName, MIN(AddressLine)
FROM
MyTable
GROUP BY
CName
If you want the first according to, say, an "inserted" column then it's a different query
SELECT
M.CName, M.AddressLine,
FROM
(
SELECT
...
Select where count of one field is greater than one
...clause, for aggregate result comparison.
Taking the query at face value:
SELECT *
FROM db.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparati...
Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
...
INSERT INTO dbo.MyTable (ID, Name)
SELECT 123, 'Timmy'
UNION ALL
SELECT 124, 'Jonny'
UNION ALL
SELECT 125, 'Sally'
For SQL Server 2008, can do it in one VALUES clause exactly as per the statement in your question (you just need to add a comma to separate eac...