MySQL，计数“填充”的数目。字段 [英] MySQL, count the number of "filled" fields in a table
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问题描述
MySQL（表）：
+----+------+
| id | text |
+----+------+
| 1 | |
+----+------+
| 2 | blah |
+----+------+
| 3 | |
+----+------+
| 4 | blah |
+----+------+
| 5 | blah |
+----+------+
PHP：
PHP:
$a = mysql_query("SELECT COUNT(*) AS count1 FROM `table`");
$b = mysql_fetch_assoc($a);
echo $b['count1'];
输出：
5
但是，我还要计算
However, I also want to count the text fields which are filled - within the same query, if possible.
结果：
5 in total
3 with filled text fields
推荐答案
SELECT COUNT(*) AS `total`, SUM(IF(`text` <> "",1,0)) AS `non_empty` FROM `table`
这篇关于MySQL，计数“填充”的数目。字段的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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