在MySQL中,COUNTIF
函數并不是一個內置的函數
以下是一些示例:
SELECT COUNT(column_name) FROM table_name;
SELECT SUM(CASE WHEN column_name = 'value' THEN 1 ELSE 0 END) as count_value FROM table_name;
SELECT SUM(CASE WHEN column_name > value THEN 1 ELSE 0 END) as count_greater_than_value FROM table_name;
SELECT SUM(CASE WHEN column_name BETWEEN value1 AND value2 THEN 1 ELSE 0 END) as count_between_values FROM table_name;
這些示例可以應用于任何數據類型,包括數字、日期和字符串。只需根據需要調整條件即可。