mysql多表查询的命令
@商牵1406：mysql 如何在多个表中查数据 -
郎红18668836329…… select a1 ,a2 from table1 where a2='班组长' union all select a1,a2 from table2 where a2='班组长' union all select a1,a2 from table3 where a2='班组长'
@商牵1406：mysql 同时查两个表 -
郎红18668836329…… 你是要干什么呢? 要把2个表关联起来查询? select tbl1.mid,tbl1.tim,tbl2.mid,tb2.tim from tbl1,tbl2 where tbl1.mid = tbl2.mid and tbl1.mid = 9 order by tbl1.tim 还是要把2个表的查询结果放到一起? select mid,tim from tbl1 where mid = 9 union select mid,tim from tbl2 where mid = 9 order by tim
@商牵1406：“mysql ”多表联合查询语句怎么写? -
郎红18668836329…… 一使用SELECT子句进行多表查询SELECT 字段名 FROM 表1,表2 … WHERE 表1字段 = 表2字段 AND 其它查询条件SELECT a.id,a.name,a.address,a.date,b.math,b.english,b.chinese FROM tb_demo065_tel AS b,tb_demo065 AS a WHERE a....
@商牵1406：mysql表太多 怎样查看所有表 -
郎红18668836329…… 到mysql控制命令台, use database_name show tables;就可以列出database_name 下的所以表! 另外可以使用第三方软件比如Navicat; 或者mysql自带winmysqladmin.exe程序也可以查看 ,如图:
@商牵1406：mysql 多表查询并排序
郎红18668836329…… 1.查询一张表: select * from 表名; 2.查询指定字段:select 字段1,字段2,字段3….from 表名; 3.where条件查询:select 字段1,字段2,字段3 frome 表名 where 条件表达式;例:select * from t_studect where id=1; select * from t_student ...
@商牵1406：mysql数据库,多个表的查询操作 -
郎红18668836329…… select a.id,b.bd,c.cd from a left join b on a.bd=b.id left join c on a.cd=c.id
@商牵1406：MYSQL多表查询语句
郎红18668836329…… select a.k1 a.n1 b.k1 b.n1 from k1 as a and k2 as b where k1.id = k2.id
@商牵1406：MySQL多表查询(超过10个相关的表) -
郎红18668836329…… 你可以试试下面这个: select * from table as a inner (join) table_2 as b on (a.ch=b.ch) inner (join) table_3 as c on (c.ch=b.ch) inner (join) table_4 as d on (d.ch =c.ch) inner (join) table_5 as e on (e.ch = d.ch) inner (join) table_6 as f on (f.ch =e.ch) ...
@商牵1406：mysql 怎么在多张表找查数据 -
郎红18668836329…… select * from help where title ='123' union all select * from new where title='123' order by date desc; 要求这2帐表的字段相同 数据类型相同.
@商牵1406：如何查询mysql数据库中有多少张表. 请您做过实验了在发答案.谢谢.systables这种就不要发了. -
郎红18668836329…… SELECT count(*) TABLES, table_schema FROM information_schema.TABLES where table_schema = 'test' GROUP BY table_schema; 将test更改成你要查找的数据库就可以了.
郎红18668836329…… select a1 ,a2 from table1 where a2='班组长' union all select a1,a2 from table2 where a2='班组长' union all select a1,a2 from table3 where a2='班组长'
@商牵1406：mysql 同时查两个表 -
郎红18668836329…… 你是要干什么呢? 要把2个表关联起来查询? select tbl1.mid,tbl1.tim,tbl2.mid,tb2.tim from tbl1,tbl2 where tbl1.mid = tbl2.mid and tbl1.mid = 9 order by tbl1.tim 还是要把2个表的查询结果放到一起? select mid,tim from tbl1 where mid = 9 union select mid,tim from tbl2 where mid = 9 order by tim
@商牵1406：“mysql ”多表联合查询语句怎么写? -
郎红18668836329…… 一使用SELECT子句进行多表查询SELECT 字段名 FROM 表1,表2 … WHERE 表1字段 = 表2字段 AND 其它查询条件SELECT a.id,a.name,a.address,a.date,b.math,b.english,b.chinese FROM tb_demo065_tel AS b,tb_demo065 AS a WHERE a....
@商牵1406：mysql表太多 怎样查看所有表 -
郎红18668836329…… 到mysql控制命令台, use database_name show tables;就可以列出database_name 下的所以表! 另外可以使用第三方软件比如Navicat; 或者mysql自带winmysqladmin.exe程序也可以查看 ,如图:
@商牵1406：mysql 多表查询并排序
郎红18668836329…… 1.查询一张表: select * from 表名; 2.查询指定字段:select 字段1,字段2,字段3….from 表名; 3.where条件查询:select 字段1,字段2,字段3 frome 表名 where 条件表达式;例:select * from t_studect where id=1; select * from t_student ...
@商牵1406：mysql数据库,多个表的查询操作 -
郎红18668836329…… select a.id,b.bd,c.cd from a left join b on a.bd=b.id left join c on a.cd=c.id
@商牵1406：MYSQL多表查询语句
郎红18668836329…… select a.k1 a.n1 b.k1 b.n1 from k1 as a and k2 as b where k1.id = k2.id
@商牵1406：MySQL多表查询(超过10个相关的表) -
郎红18668836329…… 你可以试试下面这个: select * from table as a inner (join) table_2 as b on (a.ch=b.ch) inner (join) table_3 as c on (c.ch=b.ch) inner (join) table_4 as d on (d.ch =c.ch) inner (join) table_5 as e on (e.ch = d.ch) inner (join) table_6 as f on (f.ch =e.ch) ...
@商牵1406：mysql 怎么在多张表找查数据 -
郎红18668836329…… select * from help where title ='123' union all select * from new where title='123' order by date desc; 要求这2帐表的字段相同 数据类型相同.
@商牵1406：如何查询mysql数据库中有多少张表. 请您做过实验了在发答案.谢谢.systables这种就不要发了. -
郎红18668836329…… SELECT count(*) TABLES, table_schema FROM information_schema.TABLES where table_schema = 'test' GROUP BY table_schema; 将test更改成你要查找的数据库就可以了.
