計數字段值中逗號的 MySQL 查詢?
以下是語法 -
select length(yourColumnName) - length(replace(yourColumnName, ',', '')) as anyAliasName from yourTableName;
讓我們首先建立一個表 -
mysql> create table DemoTable1510 -> ( -> Value varchar(50) -> ); Query OK, 0 rows affected (6.75 sec)
使用插入命令在表中插入一些記錄 -
mysql> insert into DemoTable1510 values('20,35');
Query OK, 1 row affected (0.57 sec)
mysql> insert into DemoTable1510 values('45,67,89');
Query OK, 1 row affected (0.99 sec)
mysql> insert into DemoTable1510 values('90,97,101,190');
Query OK, 1 row affected (1.15 sec)使用 select 語句從表中顯示所有記錄 -
mysql> select * from DemoTable1510;
這將產生以下輸出 -
+---------------+ | Value | +---------------+ | 20,35 | | 45,67,89 | | 90,97,101,190 | +---------------+ 3 rows in set (0.00 sec)
以下是統計欄位值中逗號的查詢 -
mysql> select length(Value) - length(replace(Value, ',', '')) as NumberOfComma from DemoTable1510;
這將產生以下輸出 -
+---------------+ | NumberOfComma | +---------------+ | 1 | | 2 | | 3 | +---------------+ 3 rows in set (0.00 sec)
廣告
資料結構
網路
RDBMS
作業系統
Java
iOS
HTML
CSS
Android
Python
C 程式設計
C++
C#
MongoDB
MySQL
Javascript
PHP