sql查欄位數量

Ⅰ sql 統計欄位值的數量

用分組，組內計數就可以了，意思就是根據欄位a的取值進行分組，相同的為一組，在用count進行組內計數select
a,count(*)from
agroup
by
a

Ⅱ SQL查詢欄位數量

select COUNT(a.name) from sys.all_columns a,sys.tables b
where a.object_id=b.object_id and b.name='table_name'

Ⅲ sql 查詢某一欄位值的個數

select欄位1,count(欄位2)個數
fromtabname
groupby欄位1

Ⅳ sql 查詢 不同欄位的數量

請參考下列sql語句:

select
(select count(*) from tblName
where type=100) as QtyAt100,
(select count(*) from tblName
where type=101) as qtyAt101;

或者

select
sum(case type when 100 then 1 else 0 end) as QtyAt100,
sum(case type when 101 then 1 else 0 end) as QtyAt101 from tblName
where type=100 or type=101;

Ⅳ sql中怎麼統計一個欄位的數量

sqlserver為例
創建表及插入數據
create table 姓名表(id int,u_name varchar(10),subject varchar(10))create table 科目表(id int,s_name varchar(10))insert into 姓名表 values (1,'張三','英語')insert into 姓名表 values (2,'李四','德語')insert into 姓名表 values (3,'王五','日語')insert into 姓名表 values (4,'小明','英語')insert into 姓名表 values (5,'小狗','法語')insert into 科目表 values (1,'英語')insert into 科目表 values(2,'德語')insert into 科目表 values(3,'日語')insert into 科目表 values(4,'法語')
然後需要創建一個視圖
create view v_subjectasselect a.s_name,SUM(case when a.s_name=b.subject then 1 else 0 end) countsfrom 科目表 a left join 姓名表 b on a.s_name=b.subjectgroup by a.s_name執行語句
declare @sql varchar(4000)set @sql = 'select sum(counts) as 合計'select @sql = @sql + ',sum(isnull(case [s_name] when '''+[s_name]+''' then [counts] end,0)) as ['+[s_name]+']'from (select distinct [s_name] from v_subject) as aselect @sql = @sql+' from [v_subject]'exec (@sql)結果截圖

你結果里為什麼會少呢？
這個主要是動態顯示才這么復雜，比如你在科目表裡再加個阿拉伯語，用這個也沒問題，否則用case when的寫法會比較有局限性

Ⅵ sql 查詢怎麼統計多個欄位各自的個數

--所有算的地方都用cast(個數asint)
createtabletest05
(avarchar(10),
bvarchar(10),
cvarchar(10))

insertintotest05select'#','一','三'unionall
select'@','一','三'unionall
select'￥','一','二'unionall
select'%','二','二'
select*fromtest05

selectb,COUNT(b)個數fromtest05groupbyb
selectc,COUNT(c)個數fromtest05groupbyc

selectSUM(isnull(t1.個數,0)+isnull(t2.個數,0))總數,sum(isnull(t1.個數,0))個數,t1.b,sum(isnull(t2.個數,0))個數,t2.cfrom
(selectb,COUNT(b)個數fromtest05groupbyb)ast1fulljoin
(selectc,COUNT(c)個數fromtest05groupbyc)ast2ont1.b=t2.c
groupbyt1.b,t2.c

Ⅶ sql語句統計數量 統計一個欄位出現的數量

1、創建測試表，

create table test_stu(id number, u_name varchar2(20), subject varchar2(20));

create table test_subj(id number, subject varchar2(20));