大约有 40,000 项符合查询结果（耗时：0.0287秒） [XML]
The SQL OVER() clause - when and why is it useful?
...ated values and then join it back to the original rowset, i.e. like this:
SELECT
orig.[Partition],
orig.Value,
orig.Value * 100.0 / agg.TotalValue AS ValuePercent
FROM OriginalRowset orig
INNER JOIN (
SELECT
[Partition],
SUM(Value) AS TotalValue
FROM OriginalRowset
G...
Only parameterless constructors and initializers are supported in LINQ to Entities
... where nalTmp.idDziecko == idDziec
select new Payments
{
Imie = nalTmp.Dziecko.Imie,
Nazwisko = nalTmp.Dziecko.Nazwisko,
Nazwa= ...
SQL “between” not inclusive
... is interpreted as midnight when the day starts.
One way to fix this is:
SELECT *
FROM Cases
WHERE cast(created_at as date) BETWEEN '2013-05-01' AND '2013-05-01'
Another way to fix it is with explicit binary comparisons
SELECT *
FROM Cases
WHERE created_at >= '2013-05-01' AND created_at <...
Correct way to use StringBuilder in SQL
...:
StringBuilder sb = new StringBuilder(some_appropriate_size);
sb.append("select id1, ");
sb.append(id2);
sb.append(" from ");
sb.append(table);
return sb.toString();
Note that I've listed some_appropriate_size in the StringBuilder constructor, so that it starts out with enough capacity for the f...
add column to mysql table if it does not exist
...rade_database_1_0_to_2_0()
BEGIN
-- rename a table safely
IF NOT EXISTS( (SELECT * FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=DATABASE()
AND TABLE_NAME='my_old_table_name') ) THEN
RENAME TABLE
my_old_table_name TO my_new_table_name,
END IF;
-- add a column safely
IF NO...
Restful way for deleting a bunch of items
...away with the javascript confirm on the same page, and instead, create the selection and redirect to it, showing a confirm message on that page. In other words:
From:
http://example.com/resources/
do a
POST with a selection of the ID's to:
http://example.com/resources/selections
which, if succes...
How do I view the full content of a text or varchar(MAX) column in SQL Server 2008 Management Studio
...ta.
DECLARE @S varchar(max) = 'A'
SET @S = REPLICATE(@S,100000) + 'B'
SELECT @S as [XML_F52E2B61-18A1-11d1-B105-00805F49916B]
In SSMS (at least versions 2012 to current of 18.3) this displays the results as below
Clicking on it opens the full results in the XML viewer. Scrolling to the rig...
Could not find an implementation of the query pattern
...ed to do it using:
var query = (from p in tblPersoon.Cast<Person>() select p).Single();
This kind of error (Could not find an implementation of the query pattern) usually occurs when:
You are missing LINQ namespace usage (using System.Linq)
Type you are querying does not implement IEnumer...
SQL - HAVING vs. WHERE
...ows; HAVING clause introduces a condition on aggregations, i.e. results of selection where a single result, such as count, average, min, max, or sum, has been produced from multiple rows. Your query calls for a second kind of condition (i.e. a condition on an aggregation) hence HAVING works correctl...
What is causing this ActiveRecord::ReadOnlyRecord error?
...s automatically inferred only if :joins was specified without an explicit :select nor an explicit (or finder-scope-inherited) :readonly option (see the implementation of set_readonly_option! in active_record/base.rb for Rails 2.3.4, or the implementation of to_a in active_record/relation.rb and of c...