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- postgresql - sql - count of `true` values 9 answers
- postgresql - sql - 计数`true`值9个答案
I am trying to run the following sql statement.
我试图运行以下sql语句。
SELECT
item.item_number, SUM(item.item_active)
FROM
public.item
GROUP BY item.item_number;
I am returning the following error:
我返回以下错误：
ERROR: function sum(boolean) does not exist
I figure if I can use a function to change the item.item_active to an integer, then it can take the sum of the active records.
我想如果我可以使用函数将item.item_active更改为整数，那么它可以采用活动记录的总和。
2 个解决方案
#1
6
Try boolean_col::int:
试试boolean_col :: int：
SELECT
item.item_number, SUM(item.item_active::int)
FROM
public.item
GROUP BY item.item_number;
#2
2
If that value you are getting is boolean then you can write case statement to count your active records.
如果您获得的值是布尔值，则可以编写case语句来计算活动记录。
SELECT
item.item_number, SUM(case when item.item_active then 1 else 0 end)
FROM
public.item
GROUP BY item.item_number;
#1
6
Try boolean_col::int:
试试boolean_col :: int：
SELECT
item.item_number, SUM(item.item_active::int)
FROM
public.item
GROUP BY item.item_number;
#2
2
If that value you are getting is boolean then you can write case statement to count your active records.
如果您获得的值是布尔值，则可以编写case语句来计算活动记录。
SELECT
item.item_number, SUM(case when item.item_active then 1 else 0 end)
FROM
public.item
GROUP BY item.item_number;