Set Length Control for MYSQLl database primary key

Welcome to the Linux community forum and interact with 2 million technical staff. 1. What are the problems? The JEECMS Suite (jeecms-2012-sp1) has a jeecms-db-2012-sp1. SQL file containing a jc_file table with a file_path field of 255 in length. An error is reported during installation of this suite, specific Error

Welcome to the Linux community forum and interact with 2 million technical staff> 1. What are the problems? JEECMS kit (jeecms-2012-sp1) has a jeecms-db-2012-sp1. SQL file containing a "jc_file" table with a field "file_path" with a length of 255, an error is reported during installation of this suite.

Welcome to the Linux community forum and interact with 2 million technicians>

1. Problems?

JEECMS kit (jeecms-2012-sp1) has a jeecms-db-2012-sp1. SQL file containing a "jc_file" table with a field "file_path" with a length of 255, an error is reported during installation of this suite. The specific error is as follows:

Query: create table 'jc _ file' ('file _ path' varchar (192) not null default ''comment' file path', 'file _ name' varchar (255) defau...

Error Code: 1071

Specified key was too long; max key length is 767 bytes

Execution Time: 00: 00: 00: 000

Transfer Time: 00: 00: 00: 000

Total Time: 00: 00: 00: 000

The error indicates that the length of the special key cannot exceed 767 bytes.

2. solution:

After testing, you only need to set the length of the "file_path" field to 192 or less.

3. Add the original table structure

Create table 'jc _ file '(

'File _ path' VARCHAR (255) not null default ''comment' file path ',

'File _ name' VARCHAR (255) DEFAULT ''comment' file name ',

'File _ isvalid' TINYINT (1) not null default '0' comment' valid ',

'Content _ id' INT (11) default null comment 'content id ',

Primary key ('file _ path '),

KEY 'fk _ jc_file_content '('content _ id ')

) ENGINE = innodb default charset = utf8 COMMENT = 'file resource table ';