年龄段查询，请大神帮忙看看怎么改

SELECT COUNT(*) renshu, CASE WHEN AGE <= 10 THEN '1' WHEN AGE > 10 AND AGE <= 20 THEN '2' WHEN AGE > 20 AND AGE <= 30 THEN '3' WHEN AGE > 30 AND AGE <= 40 THEN '4' WHEN AGE > 40 AND AGE <= 50 THEN '5' WHEN AGE > 50 AND AGE <= 60 THEN '6' WHEN AGE > 60 AND AGE <= 70 THEN '7' WHEN AGE > 70 AND AGE <= 80 THEN '8' WHEN AGE > 80 AND AGE <= 90 THEN '9' WHEN AGE > 90 AND AGE <= 100 THEN 'a' WHEN AGE > 100 THEN 'b' END allshuju ,OUT_MAIN_DIAG_RST leibie FROM WORK_BASY_DATA where OUT_DT >= '2014-10-01' and OUT_DT <='2014-10-31' GROUP BY allshuju这段时间里没有100以上，怎么样让100也出来显示0

SELECT COUNT(*) renshu, CASE WHEN AGE <= 10 THEN '1' WHEN AGE > 10 AND AGE <= 20 THEN '2' WHEN AGE > 20 AND AGE <= 30 THEN '3' WHEN AGE > 30 AND AGE <= 40 THEN '4' WHEN AGE > 40 AND AGE <= 50 THEN '5' WHEN AGE > 50 AND AGE <= 60 THEN '6' WHEN AGE > 60 AND AGE <= 70 THEN '7' WHEN AGE > 70 AND AGE <= 80 THEN '8' WHEN AGE > 80 AND AGE <= 90 THEN '9' WHEN AGE > 90 AND AGE <= 100 THEN 'a' WHEN AGE > 100 THEN '0' END allshuju ,OUT_MAIN_DIAG_RST leibie FROM WORK_BASY_DATA where OUT_DT >= '2014-10-01' and OUT_DT <='2014-10-31' GROUP BY allshuju

语句里不是有WHEN AGE > 100 THEN 'b' 吗？“这段时间里没有100以上，怎么样让100也出来显示0”是什么意思？

你的语句能执行吗，应该会报错的吧？你没有把MAIN_DIAG_RST包括在GROUP BY里面，另外GROUP BY不能使用别名，执行下面的语句试试

SELECT COUNT (*) renshu
    , CASE
        WHEN MONTH(DocDate) = 1 THEN '1'
        WHEN MONTH(DocDate) = 2 THEN '2'
        WHEN AGE <= 10 THEN '1'
        WHEN AGE > 10 AND AGE <= 20 THEN '2'
        WHEN AGE > 20 AND AGE <= 30 THEN '3'
        WHEN AGE > 30 AND AGE <= 40 THEN '4'
        WHEN AGE > 40 AND AGE <= 50 THEN '5'
        WHEN AGE > 50 AND AGE <= 60 THEN '6'
        WHEN AGE > 60 AND AGE <= 70 THEN '7'
        WHEN AGE > 70 AND AGE <= 80 THEN '8'
        WHEN AGE > 80 AND AGE <= 90 THEN '9'
        WHEN AGE > 90 AND AGE <= 100 THEN 'a'
        WHEN AGE > 100 THEN 'b'
    END allshuju
    , OUT_MAIN_DIAG_RST leibie
FROM WORK_BASY_DATA
WHERE OUT_DT >= '2014-10-01' AND OUT_DT <= '2014-10-31'
GROUP BY (CASE
        WHEN MONTH(DocDate) = 1 THEN '1'
        WHEN MONTH(DocDate) = 2 THEN '2'
        WHEN AGE <= 10 THEN '1'
        WHEN AGE > 10 AND AGE <= 20 THEN '2'
        WHEN AGE > 20 AND AGE <= 30 THEN '3'
        WHEN AGE > 30 AND AGE <= 40 THEN '4'
        WHEN AGE > 40 AND AGE <= 50 THEN '5'
        WHEN AGE > 50 AND AGE <= 60 THEN '6'
        WHEN AGE > 60 AND AGE <= 70 THEN '7'
        WHEN AGE > 70 AND AGE <= 80 THEN '8'
        WHEN AGE > 80 AND AGE <= 90 THEN '9'
        WHEN AGE > 90 AND AGE <= 100 THEN 'a'
        WHEN AGE > 100 THEN 'b'
    END),
    OUT_MAIN_DIAG_RST

上面的语句忘了把测试数据删了，试试下面的

SELECT COUNT (*) renshu
    , CASE
        WHEN AGE <= 10 THEN '1'
        WHEN AGE > 10 AND AGE <= 20 THEN '2'
        WHEN AGE > 20 AND AGE <= 30 THEN '3'
        WHEN AGE > 30 AND AGE <= 40 THEN '4'
        WHEN AGE > 40 AND AGE <= 50 THEN '5'
        WHEN AGE > 50 AND AGE <= 60 THEN '6'
        WHEN AGE > 60 AND AGE <= 70 THEN '7'
        WHEN AGE > 70 AND AGE <= 80 THEN '8'
        WHEN AGE > 80 AND AGE <= 90 THEN '9'
        WHEN AGE > 90 AND AGE <= 100 THEN 'a'
        WHEN AGE > 100 THEN 'b'
    END allshuju
    , OUT_MAIN_DIAG_RST leibie
FROM WORK_BASY_DATA
WHERE OUT_DT >= '2014-10-01' AND OUT_DT <= '2014-10-31'
GROUP BY (CASE
        WHEN MONTH(DocDate) = 1 THEN '1'
        WHEN MONTH(DocDate) = 2 THEN '2'
        WHEN AGE <= 10 THEN '1'
        WHEN AGE > 10 AND AGE <= 20 THEN '2'
        WHEN AGE > 20 AND AGE <= 30 THEN '3'
        WHEN AGE > 30 AND AGE <= 40 THEN '4'
        WHEN AGE > 40 AND AGE <= 50 THEN '5'
        WHEN AGE > 50 AND AGE <= 60 THEN '6'
        WHEN AGE > 60 AND AGE <= 70 THEN '7'
        WHEN AGE > 70 AND AGE <= 80 THEN '8'
        WHEN AGE > 80 AND AGE <= 90 THEN '9'
        WHEN AGE > 90 AND AGE <= 100 THEN 'a'
        WHEN AGE > 100 THEN 'b'
    END),
    OUT_MAIN_DIAG_RST