获取MySQL表中的字段数?
要显示MySQL中的字段数,请使用COUNT(*)。以下是语法-
select COUNT(*) AS anyAliasName from INFORMATION_SCHEMA.COLUMNS where table_name = yourTableName AND TABLE_SCHEMA = yourDatabaseName;
让我们首先创建一个表-
mysql> create table DemoTable794 ( ClientId int NOT NULL AUTO_INCREMENT PRIMARY KEY, ClientName varchar(100), ClientAge int, ClientCountryName varchar(100) );
以下是获取MySQL中字段数的查询-
mysql> select COUNT(*) AS TOTAL_NUMBER_OF_COLUMNS from INFORMATION_SCHEMA.COLUMNS where table_name = 'DemoTable794' AND TABLE_SCHEMA = 'web';
这将产生以下输出-
+-------------------------+ | TOTAL_NUMBER_OF_COLUMNS | +-------------------------+ | 4 | +-------------------------+ 1 row in set (0.00 sec)