相关疑难解决方法(0)

如何使用主键打印出列的"主键"？

如果表具有主键,而不是带有主键的一列和其他列在keyType中为空,则为所有列获取"主键".

   SELECT c.TABLE_NAME, 
          c.COLUMN_NAME, 
          c.DATA_TYPE, 
          c.Column_default, 
          c.character_maximum_length, 
          c.numeric_precision, 
          c.is_nullable,
          CASE 
            WHEN u.CONSTRAINT_TYPE = 'PRIMARY KEY' THEN 'primary key'
            ELSE '' 
          END AS KeyType
     FROM INFORMATION_SCHEMA.COLUMNS as c
LEFT JOIN information_schema.table_constraints as u ON c.table_name = u.table_name
 ORDER BY table_name