大约有 3,556 项符合查询结果（耗时：0.0296秒） [XML]
Row count with PDO
...et the row count using PDO in PHP? Before using PDO, I just simply used mysql_num_rows .
23 Answers
...
What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
I tried this in mysql:
14 Answers
14
...
SQL to determine minimum sequential days of access?
... 0) This works by subtracting the supplied date from zero--which Microsoft SQL Server interprets as 1900-01-01 00:00:00 and gives the number of days. This value is then re-added to the zero date yielding the same date with the time truncated.
– IDisposable
Jul ...
What does inverse_of do? What SQL does it generate?
...cumentation, it seems like the :inverse_of option is a method for avoiding SQL queries, not generating them. It's a hint to ActiveRecord to use already loaded data instead of fetching it again through a relationship.
Their example:
class Dungeon < ActiveRecord::Base
has_many :traps, :inverse_...
How to query MongoDB with “like”?
I want to query something with SQL's like query:
39 Answers
39
...
Which SQL query is faster? Filter on Join criteria or Where clause?
...
For inner joins it doesn't matter where you put your criteria. The SQL compiler will transform both into an execution plan in which the filtering occurs below the join (ie. as if the filter expressions appears is in the join condition).
Outer joins are a different matter, since the place of...
MySQL复制的概述、安装、故障、技巧、工具 - 数据库(内核) - 清泛网 - 专注...
MySQL复制的概述、安装、故障、技巧、工具同MongoDB，Redis这样的NoSQL数据库的复制相比，MySQL复制显得相当复杂！概述首先主服务器把数据变化记录到主日志，然后从服务器通过I O线...同MongoDB，Redis这样的NoSQL数据库的复制相比，M...
SQL Server CTE and recursion example
...eading an article on it. This article shows employee info with the help of Sql server CTE and recursion. It is basically showing employees and their manager info. I am not able to understand how this query works. Here is the query:
...
SELECT * FROM X WHERE id IN (…) with Dapper ORM
...
Dapper supports this directly. For example...
string sql = "SELECT * FROM SomeTable WHERE id IN @ids"
var results = conn.Query(sql, new { ids = new[] { 1, 2, 3, 4, 5 }});
share
|
...
SQL Server equivalent to MySQL enum data type?
Does SQL Server 2008 have a a data-type like MySQL's enum ?
5 Answers
5
...