在 postgresql 中将 bool 转换为 int
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Convert bool to int in postgresql
提问by Daniel L. VanDenBosch
I am trying to run the following sql statement.
我正在尝试运行以下 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_activeto an integer, then it can take the sum of the active records.
我想如果我可以使用函数将 更改item.item_active为整数，那么它可以取活动记录的总和。
回答by Gurwinder Singh
Try boolean_col::int:
尝试boolean_col::int：
SELECT
item.item_number, SUM(item.item_active::int)
FROM
public.item
GROUP BY item.item_number;
回答by Rams
If that value you are getting is boolean then you can write case statement to count your active records.
如果您获得的那个值是布尔值，那么您可以编写 case 语句来计算您的活动记录。
SELECT
item.item_number, SUM(case when item.item_active then 1 else 0 end)
FROM
public.item
GROUP BY item.item_number;
