atitit.判斷時間重疊方法總結 java c++ c#.net js php,
atitit.判斷時間重疊方法總結 java c++ c#.net js php
1. 判斷時間重疊具體流程思路 1
2. 重疊演算法 實際上就是日期集合跟個時間集合的的交集(乘法演算法) 1
3. 代碼--- 1
4. 最終產生的sql 3
5. 參考 5
1. 判斷時間重疊具體流程思路
先判斷日期重疊,在判斷時間區段重疊。
每個區段都有內包含,外包含,左包含,右包括...所以,or運算式需要4*4=16個..每個or 運算式包括4個and運算式( 兩個日期運算式,兩個時間範圍運算式)
最終的最終的的運算式需要16*4=64個,,比較長的了..
作者:: 老哇的爪子 Attilax 艾龍, EMAIL:1466519819@qq.com
轉載請註明來源: http://blog.csdn.net/attilax
2. 重疊演算法 實際上就是日期集合跟個時間集合的的交集(乘法演算法)
在程式設計裡有。。。。。
回答
那實際上就是交、並、差。
所謂加,實際上就是求兩個集合的並集
減,就是求兩個集合的差集
乘,就是求兩個集合的並集
它們都是從邏輯的運算推出來的
另外更正一下:乘是求兩個集合的交集。
3. 代碼---
private void ini() {
String db_start_fld = "start_time";
String db_end_fld = "end_time";
String db_include_exp = "db_start_fld>=ui_start and db_end_fld<=ui_end ";
String db_outclude_exp = "db_start_fld<=ui_start and db_end_fld>=ui_end ";
String db_leftinclude_exp = "db_end_fld>=ui_start and db_end_fld <=ui_end ";
String db_ritinclude_exp = "db_start_fld>=ui_start and db_end_fld<=ui_end ";
List<String> dateExpList = new ArrayList<String>() {
{
add(expandFunc(db_include_exp));
add(expandFunc(db_outclude_exp));
add(expandFunc(db_leftinclude_exp));
add(expandFunc(db_ritinclude_exp));
}
private String expandFunc(String db_include_exp) {
String db_start_fld_Datefunc = " CONVERT(varchar(100), db_start_fld, 23)";
String db_end_fld_Datefunc = " CONVERT(varchar(100), db_end_fld, 23)";
return db_include_exp.replaceAll("db_start_fld",
db_start_fld_Datefunc).replaceAll("db_end_fld",
db_end_fld_Datefunc);
}
};
List<String> timeExpList = new ArrayList<String>() {
{
add(expandFunc(db_include_exp));
add(expandFunc(db_outclude_exp));
add(expandFunc(db_leftinclude_exp));
add(expandFunc(db_ritinclude_exp));
}
private String expandFunc(String db_include_exp) {
String db_start_fld_Timefunc = " CONVERT(varchar(100), db_start_fld, 8)";
String db_end_fld_Timefunc = " CONVERT(varchar(100), db_end_fld, 8)";
return db_include_exp.replaceAll("db_start_fld",
db_start_fld_Timefunc).replaceAll("db_end_fld",
db_end_fld_Timefunc);
}
};
List<String> finalList= new ArrayList<String>() {{
for (String dateExp : dateExpList) {
for (String timeExp : timeExpList) {
this.add(dateExp+" and "+timeExp.replaceAll("db_start_fld", db_start_fld).replaceAll("db_end_fld", db_end_fld));
}
}
}};
String sql=new ArrayList(){
private String exec( ) {
String exp_final=" 1=1 ";
for (String exp : finalList) {
//if(exp_final.length()==0)
exp_final=exp_final + " or ( "+exp +" ) ";
}
return exp_final;
}}.exec( );
System.out.println(sql);
}
4. 最終產生的sql
SELECT *
FROM tab
WHERE 1=1
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), start_time, 8)<=ui_start
AND CONVERT(varchar(100), end_time, 8)>=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), end_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8) <=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)<=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)>=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)<=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)>=ui_end
AND CONVERT(varchar(100), start_time, 8)<=ui_start
AND CONVERT(varchar(100), end_time, 8)>=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)<=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)>=ui_end
AND CONVERT(varchar(100), end_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8) <=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)<=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)>=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_end_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23) <=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_end_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23) <=ui_end
AND CONVERT(varchar(100), start_time, 8)<=ui_start
AND CONVERT(varchar(100), end_time, 8)>=ui_end)
OR (CONVERT(varchar(100), db_end_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23) <=ui_end
AND CONVERT(varchar(100), end_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8) <=ui_end)
OR (CONVERT(varchar(100), db_end_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23) <=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), start_time, 8)<=ui_start
AND CONVERT(varchar(100), end_time, 8)>=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), end_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8) <=ui_end)
OR (CONVERT(varchar(100), db_start_fld, 23)>=ui_start
AND CONVERT(varchar(100), db_end_fld, 23)<=ui_end
AND CONVERT(varchar(100), start_time, 8)>=ui_start
AND CONVERT(varchar(100), end_time, 8)<=ui_end)
5. 參考
java 時間段重合時間差 - 天才少年程式員-李榮盛專欄 - 部落格頻道 - CSDN.NET
JAVA中如何判斷兩個時間段是否有交集-CSDN論壇-CSDN.NET-中國最大的IT技術社區
比較兩個日期間隔是否有碰撞的工具類,判斷兩個時間區間是否有交集(單位天) Java - 和申的日誌 - 網易部落格