行列互换的列子

行转成列的列子：需要分组求和

对于一列的行数据，数值固定的时候，可以将一列的值，拆成多列的值

select data_date, dept_id_1, sum(POR_SPAN_4),sum(POR_SPAN_7),sum(POR_SPAN_30),sum(POR_SPAN_999) ,sum(POR_SPAN_TOTAL) FROM
(SELECT 
data_date,
dept_id_1,
CASE WHEN POR_SPAN = 'POR_SPAN_4' THEN 1 ELSE 0 END as POR_SPAN_4,
CASE WHEN POR_SPAN = 'POR_SPAN_7' THEN 1 ELSE 0 END as POR_SPAN_7,
CASE WHEN POR_SPAN = 'POR_SPAN_30' THEN 1 ELSE 0 END as POR_SPAN_30,
CASE WHEN POR_SPAN = 'POR_SPAN_999' THEN 1 ELSE 0 END as POR_SPAN_999,
1 AS POR_SPAN_TOTAL
FROM

tableName ) t group by data_date, dept_id_1

注意： case when then else 使用的时候，then 和 else的类型必须一致