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What is the difference between “Class.forName()” and “Class.forName().newInstance()”?
... this:
package acme.db;
public class Driver {
static {
java.sql.DriverManager.registerDriver(new Driver());
}
...
}
Calling Class.forName("acme.db.Driver") causes the initialization of the acme.db.Driver class and thus the execution of the static initialization block. And ...
What is the difference between Integrated Security = True and Integrated Security = SSPI?
...I" used Kerberos, but they're now interchangeable.
– SqlRyan
Aug 4 '09 at 20:26
5
Didn't check la...
MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
13
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Ruby on Rails: how do I sort with two columns using ActiveRecord?
...
Assuming you're using MySQL,
Model.all(:order => 'DATE(updated_at), price')
Note the distinction from the other answers. The updated_at column will be a full timestamp, so if you want to sort based on the day it was updated, you need to use a ...
Oracle query to fetch column names
I have a mySQL query to get columns from a table like this:
12 Answers
12
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WakeLock 扩展：保持设备唤醒扩展，防止系统休眠和电池优化 · App Inventor 2 中文网
...完整唤醒锁()
获取完整的唤醒锁，保持设备完全唤醒，包括 CPU 和屏幕。
返回类型：无返回值
AquirePartialWakeLock 获取部分唤醒锁()
获取部分唤醒锁，仅保持 CPU 运行，允许屏幕关闭。
返回类型：无返回...
How can I view live MySQL queries?
How can I trace MySQL queries on my Linux server as they happen?
12 Answers
12
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...hat its not "clear which value to choose for b in each group". Why doesn't SQL put b1,b2,b3 all together in that column ?
– david blaine
Dec 22 '12 at 4:51
...
How to copy from CSV file to PostgreSQL table with headers in CSV file?
...can easily create column names and infer data types from a csv file.
from sqlalchemy import create_engine
import pandas as pd
engine = create_engine('postgresql://user:pass@localhost/db_name')
df = pd.read_csv('/path/to/csv_file')
df.to_sql('pandas_db', engine)
The if_exists parameter can be set...
How do I flush the PRINT buffer in TSQL?
I have a very long-running stored procedure in SQL Server 2005 that I'm trying to debug, and I'm using the 'print' command to do it. The problem is, I'm only getting the messages back from SQL Server at the very end of my sproc - I'd like to be able to flush the message buffer and see these messages...