大约有 6,000 项符合查询结果（耗时：0.0262秒） [XML]
How to check if mysql database exists
Is it possible to check if a (MySQL) database exists after having made a connection.
21 Answers
...
Show a number to two decimal places
...ther reasons you may want this is you dont want rounding... or in my cause SQL floats returned are not treated the same as normal floats which is a PHP math bug
– Amb3rL4nn
Feb 22 '17 at 5:48
...
PHP Constants Containing Arrays?
...e so sure they all have 5.6. Anyone on windows server just now got the 5.6 sql server drivers from microsoft about a month ago.
– M H
Jul 9 '15 at 5:28
| ...
How to concatenate columns in a Postgres SELECT?
... is not a valid operator for string concatenation in Postgres (or standard SQL). It's a private idea of Microsoft to add this to their products.
There is hardly any good reason to use character(n) (synonym: char(n)). Use text or varchar. Details:
Any downsides of using data type "text" for storin...
Correct way to pass multiple values for same parameter name in GET request
...eryset.filter(model_id__in=id_filter)
which roughly speaking performs the SQL equivalent of
WHERE model_id IN ('a', 'b')
with the first request
and,
WHERE model_id IN ('a')
with the second request.
This would work with more than 2 parameter values in the request as well !
...
Type or namespace name does not exist [closed]
... faced the same issue with an ASP.NET MVC site when I tried to use LINQ to SQL. I fixed the problem by:
Solution Explorer -> References -> Right-click on System.Data.Linq -> Copy Local (True)
share
|
...
Laravel - Eloquent or Fluent random row
...l 3:
User::order_by(DB::raw('RAND()'))->get();
Check this article on MySQL random rows. Laravel 5.2 supports this, for older version, there is no better solution then using RAW Queries.
edit 1: As mentioned by Double Gras, orderBy() doesn't allow anything else then ASC or DESC since this change....
How to find the mysql data directory from command line in windows
In linux I could find the mysql installation directory with the command which mysql . But I could not find any in windows. I tried echo %path% and it resulted many paths along with path to mysql bin.
...
MySQL Conditional Insert
...s, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the values are not already found.
Alternatively, look at the MERGE statement.
...
Postgresql: Scripting psql execution with password
How can I call psql so that it doesn't prompt for a password ?
15 Answers
15
...