大约有 48,000 项符合查询结果（耗时：0.0485秒） [XML]
Join between tables in two different databases?
...
Yes, assuming the account has appropriate permissions you can use:
SELECT <...>
FROM A.table1 t1 JOIN B.table2 t2 ON t2.column2 = t1.column1;
You just need to prefix the table reference with the name of the database it resides in.
...
c# datatable to csv
...s = dt.Columns.Cast<DataColumn>().
Select(column => column.ColumnName).
ToArray();
sb.AppendLine(string.Join(",", columnNames));
foreach (DataRow row in dt.Rows)
{
string[] fields = row.ItemArray.Select(field => fie...
What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
... then the result is the first column of the first row. An example might be SELECT @@IDENTITY AS 'Identity'.
ExecuteReader is used for any result set with multiple rows/columns (e.g., SELECT col1, col2 from sometable).
ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE...
SQL Server: Get data for only the past year
...
The following adds -1 years to the current date:
SELECT ... From ... WHERE date > DATEADD(year,-1,GETDATE())
share
|
improve this answer
|
follo...
django models selecting single field
...
thanks for the answer, what if I want to select only 1 or more fields (not all)?
– zentenk
Sep 21 '11 at 16:42
...
How to 'insert if not exists' in MySQL?
...
Solution:
INSERT INTO `table` (`value1`, `value2`)
SELECT 'stuff for value1', 'stuff for value2' FROM DUAL
WHERE NOT EXISTS (SELECT * FROM `table`
WHERE `value1`='stuff for value1' AND `value2`='stuff for value2' LIMIT 1)
Explanation:
The innermost query
SELECT *...
Check if all checkboxes are selected
How do I check if all checkboxes with class="abc" are selected?
9 Answers
9
...
Run all SQL files in a directory
...o and make sure SQLCMD Mode is enabled
Click on SQLCMD Mode; files will be selected in grey as below
:r c:\Scripts\script1.sql
:r c:\Scripts\script2.sql
:r c:\Scripts\script3.sql
Now execute
share
|
...
fs: how do I locate a parent folder?
... answered Aug 16 '11 at 18:22
Andrew HareAndrew Hare
310k6363 gold badges611611 silver badges614614 bronze badges
...
LINQPad [extension] methods [closed]
...QueryLanguage.Expression, @"from c in Customers
where c.Name.Length > 3
select c.Name", "Click to run!").Dump();
You can also write your own extension methods in LINQPad. Go to 'My Queries' and click the query called 'My Extensions'. Any types/methods that define here are accessible to all quer...