大约有 3,558 项符合查询结果（耗时：0.0222秒） [XML]
Trimming a huge (3.5 GB) csv file to read into R
...eparated) that has a lot of detail and incomplete rows (leading Access and SQL to choke). It's county level data set broken into segments, sub-segments, and sub-sub-segments (for a total of ~200 factors) for 40 years. In short, it's huge, and it's not going to fit into memory if I try to simply read...
How to enable MySQL Query Log?
How do I enable the MySQL function that logs each SQL query statement received from clients and the time that query statement has submitted?
Can I do that in phpmyadmin or NaviCat?
How do I analyse the log?
...
How to delete from multiple tables in MySQL?
...out to an EXISTS in 99% of the cases and then there is the 1% where this MySQL syntax takes the day.
share
|
improve this answer
|
follow
|
...
Call to undefined method mysqli_stmt::get_result
...
Please read the user notes for this method:
http://php.net/manual/en/mysqli-stmt.get-result.php
It requires the mysqlnd driver... if it isn't installed on your webspace you will have to work with BIND_RESULT & FETCH!
https://secure.php.net/manual/en/mysqli-stmt.bind-result.php
https://sec...
Undo changes in entity framework entities
...entity to be reverted."
I have made tests with ObjectContext.Refresh in SQL Azure, and the "RefreshMode.StoreWins" fires a query against database for each entity and causes a performance leak. Based on microsoft documentation ():
ClientWins : Property changes made to objects in the object contex...
System.Data.SQLite Close() not releasing database file
... was. I just ended up throwing an exception when you attempted to delete a SQLite DB using my library.
Anyway, this afternoon I was looking through it all again and figured I would try and find out why it was doing that once and for all, so here is what I've found so far.
What happens when you cal...
How do I use LINQ Contains(string[]) instead of Contains(string)
...perly. As written this would work for LINQ to objects (and may be LINQ to SQL). For EF, you'd do it the other way around and construct the collection in memory as List<int> instead and skip the ToString call.
– tvanfosson
Sep 28 '11 at 12:34
...
What's the difference between VARCHAR and CHAR?
What's the difference between VARCHAR and CHAR in MySQL?
14 Answers
14
...
There is already an open DataReader associated with this Command which must be closed first
...
To make a global SQL connection wide change for one query is ridiculous. The correct answer should be the ToList one below. A local fix (i.e. just change the query) for a localised problem!
– bytedev
...
How to drop all user tables?
...
I get java.lang.IllegalArgumentException: No SQL selected for execution.. My idea is that cur_rec is not declared. How to declare it since this is some consisted out of bject_name, object_type?
– lijep dam
Jun 14 '17 at 14:55
...