Error 1005, Can't Create Table...

CREATE TABLE tbl_project
(
id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(128),
description TEXT,
create_time DATETIME,
create_user_id INTEGER,
update_time DATETIME,
update_user_id INTEGER
);

CREATE TABLE IF NOT EXISTS 'tbl_issue'
(
'id' INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
'name' varchar(256) NOT NULL,
'description' varchar(2000),
'project_id' INTEGER,
'type_id' INTEGER,
'status_id' INTEGER,
'owner_id' INTEGER,
'requester_id' INTEGER,
'create_time' DATETIME,
'create_user_id' INTEGER,
'update_time' DATETIME,
'update_user_id' INTEGER
) ENGINE = InnoDB
;

CREATE TABLE IF NOT EXISTS 'tbl_user'
(
'id' INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
'email' Varchar(256) NOT NULL,
'username' Varchar(256),
'password' Varchar(256),
'last_login_time' Datetime,
'create_time' DATETIME,
'create_user_id' INTEGER,
'update_time' DATETIME,
'update_user_id' INTEGER
) ENGINE = InnoDB
;

CREATE TABLE IF NOT EXISTS 'tbl_project_user_assignment'
(
'project_id' Int(11) NOT NULL,
'user_id' Int(11) NOT NULL,
'create_time' DATETIME,
'create_user_id' INTEGER,
'update_time' DATETIME,
'update_user_id' INTEGER,
PRIMARY KEY ('project_id','user_id')
) ENGINE = InnoDB
;

ALTER TABLE 'tbl_issue' ADD CONSTRAINT 'FK_issue_project' FOREIGN KEY
('project_id') REFERENCES 'tbl_project' ('id') ON DELETE CASCADE ON
UPDATE RESTRICT;
ALTER TABLE 'tbl_issue' ADD CONSTRAINT 'FK_issue_owner' FOREIGN KEY
('owner_id') REFERENCES 'tbl_user' ('id') ON DELETE CASCADE ON UPDATE
RESTRICT;
ALTER TABLE 'tbl_issue' ADD CONSTRAINT 'FK_issue_requester' FOREIGN
KEY ('requester_id') REFERENCES 'tbl_user' ('id') ON DELETE CASCADE ON
UPDATE RESTRICT;
ALTER TABLE 'tbl_project_user_assignment' ADD CONSTRAINT 'FK_project_
user' FOREIGN KEY ('project_id') REFERENCES 'tbl_project' ('id') ON
DELETE CASCADE ON UPDATE RESTRICT;
ALTER TABLE 'tbl_project_user_assignment' ADD CONSTRAINT 'FK_user_
project' FOREIGN KEY ('user_id') REFERENCES 'tbl_user' ('id') ON
DELETE CASCADE ON UPDATE RESTRICT;

我用的mysql, 我先按照上面的语句，创建了几个表格。表格创建成功后，我设置外建的时候出现了error 1005,上网查了一下，下面是网上说的原因，但是我没找到我这里的语句哪错了，希望明白的人指点一下。

“原因之一：设置关联的字段类型不匹配，比如bigint 和 int 
  解决：外键的相关字段修改成同一类型就可以解决这个问题  
原因之二： 
解决：1. mysql支持外键约束，数据库类型必须是InnoDB 
  2. 建外键的表的列(字段)要加上index”

我这里执行没问题

show create table 看下你得表是否真得用得是innodb

mysql> CREATE TABLE tbl_project
  -> (id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
  -> name VARCHAR(128),
  -> description TEXT,
  -> create_time DATETIME,
  -> create_user_id INTEGER,
  -> update_time DATETIME,
  -> update_user_id INTEGER
  -> );
Query OK, 0 rows affected (0.13 sec)

mysql>
mysql> CREATE TABLE IF NOT EXISTS tbl_issue
  -> (id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
  -> name varchar(256) NOT NULL,
  -> description varchar(2000),
  -> project_id INTEGER,
  -> type_id INTEGER,
  -> status_id INTEGER,
  -> owner_id INTEGER,
  -> requester_id INTEGER,
  -> create_time DATETIME,
  -> create_user_id INTEGER,
  -> update_time DATETIME,
  -> update_user_id INTEGER
  -> ) ENGINE = InnoDB
  -> ;
Query OK, 0 rows affected (0.09 sec)

mysql>
mysql> CREATE TABLE IF NOT EXISTS tbl_user
  -> (id INTEGER NOT NULL PRIMARY KEY AUTO_INCREMENT,
  -> email Varchar(256) NOT NULL,
  -> username Varchar(256),
  -> password Varchar(256),
  -> last_login_time Datetime,
  -> create_time DATETIME,
  -> create_user_id INTEGER,
  -> update_time DATETIME,
  -> update_user_id INTEGER
  -> ) ENGINE = InnoDB
  -> ;
Query OK, 0 rows affected (0.11 sec)

mysql>
mysql> CREATE TABLE IF NOT EXISTS tbl_project_user_assignment
  -> (project_id Int(11) NOT NULL,
  -> user_id Int(11) NOT NULL,
  -> create_time DATETIME,
  -> create_user_id INTEGER,
  -> update_time DATETIME,
  -> update_user_id INTEGER,
  -> PRIMARY KEY (project_id,user_id)
  -> ) ENGINE = InnoDB
  -> ;
Query OK, 0 rows affected (0.13 sec)

mysql>
mysql> ALTER TABLE tbl_issue ADD CONSTRAINT FK_issue_project FOREIGN KEY
  -> (project_id) REFERENCES tbl_project (id) ON DELETE CASCADE ON
  -> UPDATE RESTRICT;
Query OK, 0 rows affected (0.20 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> ALTER TABLE tbl_issue ADD CONSTRAINT FK_issue_owner FOREIGN KEY
  -> (owner_id) REFERENCES tbl_user (id) ON DELETE CASCADE ON UPDATE
  -> RESTRICT;
Query OK, 0 rows affected (0.25 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> ALTER TABLE tbl_issue ADD CONSTRAINT FK_issue_requester FOREIGN
  -> KEY (requester_id) REFERENCES tbl_user (id) ON DELETE CASCADE ON
  -> UPDATE RESTRICT;
Query OK, 0 rows affected (0.20 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> ALTER TABLE tbl_project_user_assignment ADD CONSTRAINT FK_project_user FO
REIGN KEY (project_id) REFERENCES tbl_project (id) ON
  -> DELETE CASCADE ON UPDATE RESTRICT;
Query OK, 0 rows affected (0.20 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> ALTER TABLE tbl_project_user_assignment ADD CONSTRAINT FK_user_project FO
REIGN KEY (user_id) REFERENCES tbl_user (id) ON
  -> DELETE CASCADE ON UPDATE RESTRICT;
Query OK, 0 rows affected (0.19 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql>

建议楼主向楼上学习，直接贴出你的运行记录和结果以供他人分析。