mysql - sql如何查询字段中有内容的数据

Question

sql如何查询字段中有内容的数据。 想统计都有哪些用户填了某个字段。求方法

Answer 1

SELECT * FROM table_name WHERE column_name IS NOT NULL

or

SELECT * FROM table_name WHERE column_name <> ''

Select based on your column type and default value.

Answer 2

# 字段默认值为 NULL的情形 start
# 判断member表里user_name为空情况下的用户数
SELECT count(*) FROM member WHERE user_name IS NULL;
# 判断member表里user_name不为空情况下的用户数
SELECT count(*) FROM member WHERE user_name IS NOT NULL;
# 字段默认值为 NULL的情形 end

# 字段默认值为空字符串的情形 start
# 判断member表里user_name为空情况下的用户数
SELECT count(*) FROM member WHERE user_name = '';
# 判断member表里user_name不为空情况下的用户数
SELECT count(*) FROM member WHERE user_name <> '';
# 字段默认值为空字符串的情形 end

Answer 3

select * from table where XX is not null  and XX<>' '

There are spaces in the quotation marks, and the answer has received rave reviews!