ActiveRecord数据类型的文档页面在哪里？

Question

我找不到包含所有数据类型列表的活动记录文档页面.

有人可以帮我吗？

Answer 1

如果您正在讨论迁移的类型,例如字符串,整数,日期时间等,那么您需要ActiveRecord :: ConnectionAdapters :: TableDefinition,列方法.(Rails的5编辑:又见连接add_column.)

截至本次更新,标准类型为:

• :primary_key
• :string
• :text
• :integer
• :bigint
• :float
• :decimal
• :numeric
• :datetime
• :time
• :date
• :binary
• :boolean

:decimal每个数据库的实现都不同,所以如果可能的话我会避免它.您可以使用不在此列表中的类型,只要数据库支持该类型(例如,:polygon在MySQL中),但这不是数据库不可知的,也应该避免.

Answer 2

您还可以在源中查看ActiveRecord数据类型.每个DBMS适配器都包含自己的映射.例如,在MySQL的情况下,请查看此文件:https://github.com/rails/rails/blob/master/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb#L148或通过此行代码获取当前文件DBMS适配器:

ActiveRecord::Base.connection.native_database_types.keys

Answer 3

这是数据库适配器的类型的默认映射：

Answer 4

请注意，这是基于 2015 年 2 月 13 日的 Rails 源代码（Rails 4.2）

如果有人想查看这些数据类型如何映射到您正在使用的数据库中。

您可以在 github 上轻松获取 rails 源代码。

例如

Rails 数据类型到 mysql 数据类型的映射。

NATIVE_DATABASE_TYPES = {
        :primary_key => "int(11) auto_increment PRIMARY KEY",
        :string      => { :name => "varchar", :limit => 255 },
        :text        => { :name => "text" },
        :integer     => { :name => "int", :limit => 4 },
        :float       => { :name => "float" },
        :decimal     => { :name => "decimal" },
        :datetime    => { :name => "datetime" },
        :time        => { :name => "time" },
        :date        => { :name => "date" },
        :binary      => { :name => "blob" },
        :boolean     => { :name => "tinyint", :limit => 1 }
      }

位于https://github.com/rails/rails/blob/master/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb#L148

如果有人想要 postgreSQL，你就去吧。

NATIVE_DATABASE_TYPES = {
        primary_key: "serial primary key",
        bigserial: "bigserial",
        string:      { name: "character varying" },
        text:        { name: "text" },
        integer:     { name: "integer" },
        float:       { name: "float" },
        decimal:     { name: "decimal" },
        datetime:    { name: "timestamp" },
        time:        { name: "time" },
        date:        { name: "date" },
        daterange:   { name: "daterange" },
        numrange:    { name: "numrange" },
        tsrange:     { name: "tsrange" },
        tstzrange:   { name: "tstzrange" },
        int4range:   { name: "int4range" },
        int8range:   { name: "int8range" },
        binary:      { name: "bytea" },
        boolean:     { name: "boolean" },
        bigint:      { name: "bigint" },
        xml:         { name: "xml" },
        tsvector:    { name: "tsvector" },
        hstore:      { name: "hstore" },
        inet:        { name: "inet" },
        cidr:        { name: "cidr" },
        macaddr:     { name: "macaddr" },
        uuid:        { name: "uuid" },
        json:        { name: "json" },
        jsonb:       { name: "jsonb" },
        ltree:       { name: "ltree" },
        citext:      { name: "citext" },
        point:       { name: "point" },
        bit:         { name: "bit" },
        bit_varying: { name: "bit varying" },
        money:       { name: "money" },
      }