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SQL Server Linked Server Example Query
...a Linked Server in SSMS Object Explorer, right-click, and Script Table as, SELECT To, and New Query Editor Window. The resulting SELECT statement will include the correct, fully-qualified path to the table. I had a mystery database qualifier in working with Sybase and this gave me the correct name.
...
Group by in LINQ
... p in persons
group p.car by p.PersonId into g
select new { PersonId = g.Key, Cars = g.ToList() };
Or as a non-query expression:
var results = persons.GroupBy(
p => p.PersonId,
p => p.car,
(key, g) => new { PersonId = key, Cars = g.ToList() });
...
How to get a list of column names on Sqlite3 database?
...
but you can't select from that table. It's just plain annoying. I'm trying something like this... but it don't work create temporary table TmpCols (cid integer, name text, type text, nn bit, dflt_value, pk bit); .mode insert TmpCols .out...
Function vs. Stored Procedure in SQL Server
...-----------+----------------------------------------+
| We can't use SP in SELECT/ | We can use UDF in SELECT/ WHERE/ |
| WHERE/ HAVING statement. | HAVING statement. |
+---------------------------------+----------------------------------------+
| We can use ex...
Mysql order by specific ID values
... use ORDER BY and FIELD function.
See http://lists.mysql.com/mysql/209784
SELECT * FROM table ORDER BY FIELD(ID,1,5,4,3)
It uses Field() function, Which "Returns the index (position) of str in the str1, str2, str3, ... list. Returns 0 if str is not found" according to the documentation. So actual...
Postgres and Indexes on Foreign Keys and Primary Keys
...hema(s) from your program, all the information is on hand in the catalog:
select
n.nspname as "Schema"
,t.relname as "Table"
,c.relname as "Index"
from
pg_catalog.pg_class c
join pg_catalog.pg_namespace n on n.oid = c.relnamespace
join pg_catalog.pg_index ...
How do you convert a DataTable into a generic list?
...ataTable
//using lamdaexpression
emp = (from DataRow row in dt.Rows
select new Employee
{
_FirstName = row["FirstName"].ToString(),
_LastName = row["Last_Name"].ToString()
}).ToList();
share
...
How do you configure an OpenFileDialog to select folders?
In VS .NET, when you are selecting a folder for a project, a dialog that looks like an OpenFileDialog or SaveFileDialog is displayed, but is set up to accept only folders. Ever since I've seen this I've wanted to know how it's done. I am aware of the FolderBrowserDialog, but I've never really like...
mysql :: insert into table, data from another table?
...
INSERT INTO action_2_members (campaign_id, mobile, vote, vote_date)
SELECT campaign_id, from_number, received_msg, date_received
FROM `received_txts`
WHERE `campaign_id` = '8'
share
|
imp...
What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
...ent attribute. Otherwise, (valid at least for PG) you might get ERROR: for SELECT DISTINCT, ORDER BY expressions must appear in select list
– long
Apr 21 at 14:08
add a commen...