大约有 46,000 项符合查询结果（耗时：0.0292秒） [XML]
Query to count the number of tables I have in MySQL
...
SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'dbName';
Source
This is mine:
USE databasename;
SHOW TABLES;
SELECT FOUND_ROWS();
...
How can I return two values from a function in Python?
...s, but you can return a tuple or a list and unpack it after the call:
def select_choice():
...
return i, card # or [i, card]
my_i, my_card = select_choice()
On line return i, card i, card means creating a tuple. You can also use parenthesis like return (i, card), but tuples are created ...
Populating a razor dropdownlist from a List in MVC
...leaner separation.
First create a viewmodel to store the Id the user will select along with a list of items that will appear in the DropDown.
ViewModel:
public class UserRoleViewModel
{
// Display Attribute will appear in the Html.LabelFor
[Display(Name = "User Role")]
public int Sele...
Select distinct using linq [duplicate]
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myList.GroupBy(test => test.id)
.Select(grp => grp.First());
Edit: as getting this IEnumerable<> into a List<> seems to be a mystery to many people, you can simply write:
var result = myList.GroupBy(test => test.id)
.S...
How do I get list of all tables in a database using TSQL?
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SQL Server 2000, 2005, 2008, 2012, 2014, 2016, 2017 or 2019:
SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE'
To show only tables from a particular database
SELECT TABLE_NAME
FROM <DATABASE_NAME>.INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'...
SQL Call Stored Procedure for each Row without using a cursor
...rate over all customers
WHILE (1 = 1)
BEGIN
-- Get next customerId
SELECT TOP 1 @CustomerID = CustomerID
FROM Sales.Customer
WHERE CustomerID > @CustomerId
ORDER BY CustomerID
-- Exit loop if no more customers
IF @@ROWCOUNT = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC...
SQL DROP TABLE foreign key constraint
...your table, you could use this SQL (if you're on SQL Server 2005 and up):
SELECT *
FROM sys.foreign_keys
WHERE referenced_object_id = object_id('Student')
and if there are any, with this statement here, you could create SQL statements to actually drop those FK relations:
SELECT
'ALTER TABL...
How to comment out a block of Python code in Vim
...to allow me to indent certain lines of code (whether those lines have been selected in visual mode, or n lines above/below current cursor position).
...
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 | ...
How to print SQL statement in codeigniter model
...veRecord generated SQL:
Before the query runs:
$this->db->_compile_select();
And after it has run:
$this->db->last_query();
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