问题
I used mysqldump to export my database and then I imported it into MySQL on my other server. I can now see all my tables if I do "show tables" but I can't actually select from or describe any of them.
ERROR 1146 (42S02): Table 'mydatabase.user' doesn't exist
All of my tables are InnoDB. I saw one issue people had where they were using old_passwords, so I explicitly set that to 0 in my.cnf and I made sure all of the passwords in the mysql table were 41 hexadecimal digits as they should be for the new passwords.
回答1:
The reason "show tables;" works is because mysqld will scan the database directory for .frm files only. As long as they exist, it sees a table definition.
If you imported the data into MySQL and this error message happens, the first thing I would immediately do is run this command: (BTW This is MySQL 5.1.45, but works in MySQL 5.x anyway)
mysql> show engines;
+------------+---------+----------------------------------------------------------------+--------------+------+------------+
| Engine | Support | Comment | Transactions | XA | Savepoints |
+------------+---------+----------------------------------------------------------------+--------------+------+------------+
| InnoDB | YES | Supports transactions, row-level locking, and foreign keys | YES | YES | YES |
| MRG_MYISAM | YES | Collection of identical MyISAM tables | NO | NO | NO |
| BLACKHOLE | YES | /dev/null storage engine (anything you write to it disappears) | NO | NO | NO |
| CSV | YES | CSV storage engine | NO | NO | NO |
| MEMORY | YES | Hash based, stored in memory, useful for temporary tables | NO | NO | NO |
| FEDERATED | NO | Federated MySQL storage engine | NULL | NULL | NULL |
| ARCHIVE | YES | Archive storage engine | NO | NO | NO |
| MyISAM | DEFAULT | Default engine as of MySQL 3.23 with great performance | NO | NO | NO |
+------------+---------+----------------------------------------------------------------+--------------+------+------------+
8 rows in set (0.00 sec)
If the server you imported the data into says InnoDB is disabled, then you have a big problem. Here is what you should do:
1) Drop all the Data from the New Import DB Server
2) Cleanup InnoDB Setup
3) run SHOW ENGINES; and make sure InnoDB is fully operational !!!
4) Reload the mysqldump into the new import server
Give it a Try !!!
回答2:
I had this problem when I changed from a windows server to a Linux server. Tables are files, and windows files are case insesitive, but linux files are case sensitive.
In my aplication, in the sql queries, some times I used uppercase tablenames and other times lowercase, so, sometimes I obtained the same result as you.
回答3:
I my case it was SQLCA.DBParm parameter.
I used SQLCA.DBParm = "Databse = "sle_database.text"" but it must be
SQLCA.DBParm = "Database='" +sle_database.text+ "'"
Explain : you are going to combine three strings :
a) Database=' - "Database='"
b) (name of the database) - +sle_database.text+
c) ' - "'"
来源：https://stackoverflow.com/questions/6128286/innodb-tables-exist-in-mysql-but-says-they-do-not-exist-after-copying-database-t