mysql中怎么查询表中的字段个数？

[JAVA_STU]

mysql中怎么查询表中的字段个数？

[wwwwb]

如果是5以上，可以直接查询系统表
sELECT table_name, table_type, engine
FROM information_schema.tables
WHERE table_schema = 'databasename' and table_name='tablename'
ORDER BY table_name DESC;

[vipper23]

select count(1) from columns where table_name =要查的表的名字;

[ACMAIN_CHM]

方法一，在你的程序中直接
desc tablename

然后总行数就是你的字段数。

mysql> desc ysks;
+-------+---------------+-----
| Field | Type          | Null
+-------+---------------+-----
| 单号  | int(11)       | YES
| 金额  | decimal(10,2) | YES
| 已收  | decimal(10,2) | YES
| 日期  | bigint(20)    | YES
| 名称  | varchar(10)   | YES
| 余额  | decimal(10,2) | YES
| 备注  | varchar(10)   | YES
| 品名  | varchar(10)   | YES
+-------+---------------+-----
8 rows in set (0.06 sec)

mysql> select FOUND_ROWS();
+--------------+
| FOUND_ROWS() |
+--------------+
|            8 |
+--------------+
1 row in set (0.06 sec)

mysql>

[ACMAIN_CHM]

方法二，通过系统表information_schema.`COLUMNS` ( mysql5以上版本支持)

mysql> select count(*) from information_schema.`COLUMNS`
    -> where TABLE_SCHEMA='csdn'
    -> and TABLE_NAME='ysks';
+----------+
| count(*) |
+----------+
|        8 |
+----------+
1 row in set (0.06 sec)

mysql>

[wwwwb]

select count(*) from information_schema.columns where table_schema='databasename' and table_
name='tablename' ;

[JAVA_STU]

[Quote=引用 5 楼 wwwwb 的回复:]
select count(*) from information_schema.columns where table_schema='databasename' and table_
name='tablename' ;
[/Quote]
查出来了，3q。