加入两个表和count -statistics [英] Join two tables and count -statistics

问题描述

需要编写显示统计信息的Mysql查询，



描述：

父表60 lac记录包含唯一记录

包含1亿卢比的子表包含多个记录

Need to write Mysql query showing statistics,

Description:
Parent table 60 lac records contains unique records
Child table with 1 crore Contains multiple records

 Parent Table
 ID  Flag1 Flag2
 1    1      1
 2    NULL   1
 3    1      1 

Child Table
 ID acc Category
  1 101  Cate1
  1 102  Cate5
  2 103  Cate2
  2 104  Cate3
  3 105  Cate4
  3 106  Cate4 

两张桌子之间的一对多关系。



我需要通过查询编写组来查找使用MySQL数据库的一个查询中的分类和基于标志的计数

样本：

我尝试过以下查询但是我不想写每个类别的条件和Flag作为Child表包含30个类别和12个标志

One to many relationship between two tables.

I need to write group by queries to find categoriwise and flag based count in one query with MySQL Database
sample:
I have tried with following query but i dont want to write where condition for each category and Flag as Child table contains 30 categories and 12 Flags

select count(1) from Parent A,Child B where A.ID=B.ID AND B.Category='CATE1' and A.Flag1=1

预期结果

Result expected

Category  Flag1_Count Flag2_Count
  Cate1       1           0 
  Cate2       0           1
  Cate3       1           1

请帮助。

Please help.

推荐答案

查询将如下所示

The query will be like as follows

SELECT B.Category, Count(A.Flag1) AS Flag1_Count,  Count(A.Flag2) AS Flag2_Count FROM Parent A 
INNER JOIN Child B WHERE A.ID=B.ID 
GROUP BY B.Category;

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