我有迁移:
lass ChangeDefaultValueBodyForBlogPosts < ActiveRecord::Migration
def up
change_column :blog_posts, :body, :text, :null => false
change_column :comments, :text, :text, :null => false
end
def down
change_column :comments, :text, :text, :default => nil
change_column :blog_posts, :body, :text, :default => nil
end
end
rake db:migrate display error:
Mysql2 ::错误:BLOB,TEXT,GEOMETRY或JSON列'body'不能有默认值:ALTER TABLE blog_posts
CHANGE body
body
text DEFAULT ''NOT NULL / home / user / projects / projectname / db / migrate / 20120508203410_change_default_value_body_for_blog_posts.rb:3:in up up
我使用的是ubuntu 16.04,
mysql server 5.7(版本:5.7.12-0ubuntu1.1 版本:5.7.12-0ubuntu1 版本:5.7.11-0ubuntu6 )
我在谷歌看了一下,解决这个问题需要改变SQL模式= “STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION”
到
sql-mode="NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
但my.conf文件为空。
#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
#
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
#
# * IMPORTANT: Additional settings that can override those from this file!
# The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/
!includedir /etc/mysql/mysql.conf.d/
如何解决这个问题,请帮忙。谢谢。
答案 0 :(得分:1)
我找到了解决方案: 需要在my.cnf中添加
[mysqld]
sql-mode="NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
答案 1 :(得分:0)
你需要找到正确的my.cnf:
sudo find / -name "*.cnf"
/etc/mysql/mysql.conf.d/mysqld.cnf
/etc/mysql/my.cnf
/etc/mysql/mysql.cnf
/etc/mysql/conf.d/mysqldump.cnf
/etc/mysql/conf.d/mysql.cnf
我根据
编辑了/etc/mysql/mysql.conf.d/mysqld.cnfstrace mysql ";" 2>&1 | grep cnf
stat("/etc/my.cnf", 0x7ffda9472660) = -1 ENOENT (No such file or directory)
stat("/etc/mysql/my.cnf", {st_mode=S_IFREG|0644, st_size=683, ...}) = 0
open("/etc/mysql/my.cnf", O_RDONLY) = 3
stat("/etc/mysql/conf.d/mysql.cnf", {st_mode=S_IFREG|0644, st_size=8, ...}) = 0
open("/etc/mysql/conf.d/mysql.cnf", O_RDONLY) = 4
stat("/etc/mysql/conf.d/mysqldump.cnf", {st_mode=S_IFREG|0644, st_size=55, ...}) = 0
open("/etc/mysql/conf.d/mysqldump.cnf", O_RDONLY) = 4
stat("/etc/mysql/mysql.conf.d/mysqld.cnf", {st_mode=S_IFREG|0644, st_size=3034, ...}) = 0
open("/etc/mysql/mysql.conf.d/mysqld.cnf", O_RDONLY) = 4
stat("/etc/mysql/mysql.conf.d/mysqld_safe_syslog.cnf", {st_mode=S_IFREG|0644, st_size=21, ...}) = 0
open("/etc/mysql/mysql.conf.d/mysqld_safe_syslog.cnf", O_RDONLY) = 4
stat("/root/.my.cnf", 0x7ffda9472660) = -1 ENOENT (No such file or directory)
stat("/root/.mylogin.cnf", 0x7ffda9472660) = -1 ENOENT (No such file or directory)
找到正确的文件后,在[mysqld]声明下面添加 sql-mode =&#34; NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION&#34;
答案 2 :(得分:0)
使用xampp的mysql在本地计算机上进行迁移时,我没有任何问题。仅在生产服务器上,它才开始出现故障。我发现xampp运行mariadb而不是普通的mysql。因此,在服务器上使用mariaDB解决了我的问题。
答案 3 :(得分:0)
再次检查您的sql代码错误,上面的“ body”明确表示不是默认值
示例:
`completed` text NOT NULL DEFAULT 'false',
删除默认值
后`completed` text NOT NULL,
现在希望您的错误已消失。 对不起我的英语。
答案 4 :(得分:0)
我是这样解决这个问题的:我曾经想在一台服务器上导出我的mySql数据库,然后在另一台服务器(CPanel主机)中导入它。每次我尝试时,phpMyAdmin 都会在其中一个数据库表的字段之一上出现此错误。然后我去了我的源主机;打开 phpMyAdmin 并打开该表结构并删除该字段的默认值。然后我再次导出,这次成功了。