SQL统计1-12月的数据，没有数据的月份显示为0

1.利用临时表补足数据（HANA）

select A.DATAYEAR as DATAYEAR, A.DATAMONTH as DATAMONTH,sum(DATANUM) as DATANUM from 
(select YEAR(GL_LZ_XKTZ_NY) as DATAYEAR,Month(GL_LZ_XKTZ_NY) as DATAMONTH,count(*) as DATANUM
from TableName
where Year(GL_LZ_XKTZ_NY) >= year(ADD_YEARS(current_date,-1)) and  Year(GL_LZ_XKTZ_NY) <= year(current_date)
group by YEAR(GL_LZ_XKTZ_NY) , Month(GL_LZ_XKTZ_NY)  
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 1  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 2  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 3  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 4  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 5  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 6  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 7  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 8  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 9  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 10  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 11  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(ADD_YEARS(current_date,-1)) as DATAYEAR, 12  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 1  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 2  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 3  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 4  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 5  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 6  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 7  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 8  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 9  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 10  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 11  as DATAMONTH , 0  as DATANUM from DUMMY
union 
select year(current_date) as DATAYEAR, 12  as DATAMONTH , 0  as DATANUM from DUMMY
)A 
group by A.DATAYEAR,A.DATAMONTH 
order by A.DATAYEAR,A.DATAMONTH   

注：DUMMY 是虚表、临时表

2.新建一张表，表中只有一个字段，只有12行数据，即（1,2,3,4,5...12）,然后左链接需要统计的数据表。
3.利用Case When Else End 枚举：(月份显示在表名上)(SQL)

select 'Title' as 'dataTitle',
isnull(sum(case when month = '1' then ThisMonthPassNum else 0 end),0) as 'month1' ,
isnull(sum(case when month = '2' then ThisMonthPassNum else 0 end),0) as 'month2' ,
isnull(sum(case when month = '3' then ThisMonthPassNum else 0 end),0) as 'month3' ,
isnull(sum(case when month = '4' then ThisMonthPassNum else 0 end),0) as 'month4' ,
isnull(sum(case when month = '5' then ThisMonthPassNum else 0 end),0) as 'month5' ,
isnull(sum(case when month = '6' then ThisMonthPassNum else 0 end),0) as 'month6' ,
isnull(sum(case when month = '7' then ThisMonthPassNum else 0 end),0) as 'month7' ,
isnull(sum(case when month = '8' then ThisMonthPassNum else 0 end),0) as 'month8' ,
isnull(sum(case when month = '9' then ThisMonthPassNum else 0 end),0) as 'month9' ,
isnull(sum(case when month = '10' then ThisMonthPassNum else 0 end),0) as 'month10' ,
isnull(sum(case when month = '11' then ThisMonthPassNum else 0 end),0) as 'month11' ,
isnull(sum(case when month = '12' then ThisMonthPassNum else 0 end),0) as 'month12' 
from TableName