$ export NLS_LANG=AMERICAN_AMERICA.AL32UTF8
使用sqlloader ，导入成功，不再报错！
可能原因是：
AL32UTF8：一个汉字占三个字节；
ZHS16GBK：一个汉字占两个字节；
因为数据中有中文，考虑数据无法导入是字符集的问题。使用sqlloader ，导入成功，不再报错！检查control文件和表结构都一一对应。AL32UTF8：一个汉字占三个字节；ZHS16GBK：一个汉字占两个字节；
Many SQL texts attempt to serve as an encyclopedic reference on SQL syntax — an approach that is often counterproductive, because that information is readily available in online references published by the major database vendors.
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Learn How To…
Use SQL to retrieve data from relational databases
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有这么一个数据，按照一分钟统计数据的查询数，字段内容：
stat_date date, stat_num number(10)
stat_date表示统计日期，stat_num表示统计数目
数据如下：
2009-0...
1. sql loader里有几个概念：
控制文件：和数据库的文件不是一回事，个人理解是用于数据加载控制的。
数据文件：要加载入库的数据文件，支持文本，csv, 等格式。 数据文件的内容可以放在控制文件的最后。
×注意：最好数据记录之间不
最近做javaWeb项目，出现了一个小插曲java.sql.SQLException: Column ’ name ’ not found，首先分析出现小插曲的本质问题：
1、查询语句是否有问题
2、是否有name
3、或者就是实体映射问题,实体类没有name
就拿我当时的小插曲做个简单分析喽！
首先我的查询语句：findRownumberMax="SELECT MAX(rownumbername...
The logical '||' operator is used in programming languages to perform a logical OR operation. When using the '||' operator, if any of the operands (either constant or variable) evaluate to true, the result of the expression will be true. If both operands are false, then the result will be false.
Here's an example of using the logical '||' operator with a constant operand in C++:
```cpp
#include <iostream>
using namespace std;
int main() {
int age = 25;
if (age < 18 || age > 60) {
cout << "You are either under 18 or over 60." << endl;
} else {
cout << "You are between 18 and 60." << endl;
return 0;
In this example, the logical OR operator '||' is used to check if the age variable is either less than 18 or greater than 60. If either condition is true, the message "You are either under 18 or over 60" will be displayed. Otherwise, the message "You are between 18 and 60" will be displayed.
You can also use constants as operands with the logical '||' operator in a similar way to variables. The behavior remains the same; if any of the operands (constant or variable) evaluate to true, the overall result will be true.
