大约有 40,000 项符合查询结果（耗时：0.0208秒） [XML]
Generate GUID in MySQL for existing Data?
...e BEFORE UPDATE on YourTable
FOR EACH ROW
BEGIN
SET new.guid_column := (SELECT UUID());
END
//
Then execute
UPDATE YourTable set guid_column = (SELECT UUID());
And DROP TRIGGER beforeYourTableUpdate;
UPDATE
Another solution that doesn't use triggers, but requires primary key or unique inde...
PHP method chaining?
...imed at creating a DSL. Ex: $foo->setBar(1)->setBaz(2) vs $table->select()->from('foo')->where('bar = 1')->order('ASC). The latter spans multiple objects.
– Gordon
Sep 16 '10 at 7:32
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how to use ng-option to set default value of select element
I've seen the documentation of the Angular select directive here: http://docs.angularjs.org/api/ng.directive:select .
I can't figure how to set the default value. This is confusing:
...
Delete duplicate rows from small table
...
DELETE FROM dupes a
WHERE a.ctid <> (SELECT min(b.ctid)
FROM dupes b
WHERE a.key = b.key);
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How can I get a list of all functions stored in the database of a particular schema in PostgreSQL?
...
SELECT n.nspname as "Schema", p.proname as "Name", pg_catalog.pg_get_function_result(p.oid) as "Result data type", pg_catalog.pg_get_function_arguments(p.oid) as "Argument data types", CASE WHEN p.proisagg THEN 'agg'...
SQL “select where not in subquery” returns no results
...MySQL
There are three ways to do such a query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM ...
Making a WinForms TextBox behave like your browser's address bar
...etty straightforward and seems to work in all the scenarios (mousing down, selecting text, tabbing focus, etc.)
bool alreadyFocused;
...
textBox1.GotFocus += textBox1_GotFocus;
textBox1.MouseUp += textBox1_MouseUp;
textBox1.Leave += textBox1_Leave;
...
void textBox1_Leave(object sender, EventAr...
Get names of all files from a folder with Ruby
...ng subdirectories and ".", ".." dotted folders:
Dir.entries("your/folder").select { |f| File.file? File.join("your/folder", f) }
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How does one reorder columns in a data frame?
...
You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...
jQuery get specific option tag text
...Here is this answer expanded if you want to get the value dynamically: var selectValue = document.getElementById('list').value; var selectOption = $("#list option[value=" + selectValue + "]").text(); ///good example nickf.
– Kevin Florida
Apr 5 '11 at 13:48
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