大约有 41,000 项符合查询结果（耗时：0.0308秒） [XML]
Good Hash Function for Strings
...ng it might be a good idea to sum up the unicode values for the first five characters in the string (assuming it has five, otherwise stop where it ends). Would that be a good idea, or is it a bad one?
...
Execute stored procedure with an Output parameter?
...s to right-click on the procedure in Sql Server Management Studio(SSMS),
select execute stored procedure...
and add values for the input parameters as prompted.
SSMS will then generate the code to run the proc in a new query window, and execute it for you. You can study the generated code to se...
Check if table exists in SQL Server
...nge from version to version.
To check if a table exists use:
IF (EXISTS (SELECT *
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'TheSchema'
AND TABLE_NAME = 'TheTable'))
BEGIN
--Do Stuff
END
...
Using IQueryable with Linq
...ram. Your program then filters the data. In essence, the database does a SELECT * FROM Products, and returns EVERY product to you.
With the right IQueryable<T> provider, on the other hand, you can do:
IQueryable<Product> products = myORM.GetQueryableProducts();
var productsOver25 =...
D3.js: How to get the computed width and height for an arbitrary element?
...d height for an arbitrary g element in my SVG because I need to draw a selection marker around it once the user has clicked it.
...
How to insert text into the textarea at the current cursor position?
...ction insertAtCursor(myField, myValue) {
//IE support
if (document.selection) {
myField.focus();
sel = document.selection.createRange();
sel.text = myValue;
}
//MOZILLA and others
else if (myField.selectionStart || myField.selectionStart == '0') {
...
Click button copy to clipboard using jQuery
...browsers because most browsers have the ability to programmatically copy a selection of text to the clipboard using document.execCommand("copy") that works off a selection.
As with some other actions in a browser (like opening a new window), the copy to clipboard can only be done via a specific use...
Drop all tables whose names begin with a certain string
...n one in the database.
DECLARE @cmd varchar(4000)
DECLARE cmds CURSOR FOR
SELECT 'drop table [' + Table_Name + ']'
FROM INFORMATION_SCHEMA.TABLES
WHERE Table_Name LIKE 'prefix%'
OPEN cmds
WHILE 1 = 1
BEGIN
FETCH cmds INTO @cmd
IF @@fetch_status != 0 BREAK
EXEC(@cmd)
END
CLOSE cmds;
DEA...
What is the best way to paginate results in SQL Server
... sake of this example, let's assume that the query you're dealing with is
SELECT * FROM Orders WHERE OrderDate >= '1980-01-01' ORDER BY OrderDate
In this case, you would determine the total number of results using:
SELECT COUNT(*) FROM Orders WHERE OrderDate >= '1980-01-01'
...which may ...
How to add column if not exists on PostgreSQL?
...s, _col text, _type regtype)
RETURNS bool AS
$func$
BEGIN
IF EXISTS (SELECT 1 FROM pg_attribute
WHERE attrelid = _tbl
AND attname = _col
AND NOT attisdropped) THEN
RETURN FALSE;
ELSE
EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...