🧩 SQL 建表语句转 C# 实体类SQL CREATE TABLE to C# Class

使用说明与常见问题How-to & FAQ

「SQL 建表语句转 C# 实体类」是什么？What is the SQL CREATE TABLE to C# Class tool?

把 MySQL、SQL Server、PostgreSQL、Oracle 的 CREATE TABLE 语句转换成 C# 实体类：自动映射字段类型、可空类型、注释，可选 Entity Framework 数据注解和 record 写法。Turn MySQL, SQL Server, PostgreSQL or Oracle CREATE TABLE statements into C# entity classes with mapped types, nullable types and comments, plus optional Entity Framework data annotations or records.

如何使用「SQL 建表语句转 C# 实体类」？How do I use the SQL CREATE TABLE to C# Class?

粘贴一条或多条 CREATE TABLE 语句（可直接用 SHOW CREATE TABLE 或数据库工具导出的 DDL），设置命名空间和选项，右侧即生成对应的 C# 类。字段注释（COMMENT）会变成 XML 文档注释。Paste one or more CREATE TABLE statements (e.g. from SHOW CREATE TABLE or a DDL export), set the namespace and options, and the C# classes appear below. Column COMMENTs become XML doc comments.

数据库类型是怎么对应到 C# 的？How are SQL types mapped to C#?

int→int，bigint→long，tinyint(1)/bit→bool，decimal/numeric/money→decimal，float/double→double，real→float，char/varchar/text→string，date/datetime/timestamp→DateTime，datetimeoffset/timestamptz→DateTimeOffset，uuid/uniqueidentifier→Guid，blob/varbinary/bytea→byte[]；unsigned 会用对应的无符号类型。int→int, bigint→long, tinyint(1)/bit→bool, decimal/numeric/money→decimal, float/double→double, real→float, char/varchar/text→string, date/datetime/timestamp→DateTime, datetimeoffset/timestamptz→DateTimeOffset, uuid/uniqueidentifier→Guid, blob/varbinary/bytea→byte[]; unsigned columns use unsigned types.

什么时候生成 int? 这样的可空类型？When are nullable types like int? used?

没有 NOT NULL（也不是主键）的列会生成可空类型。值类型总是加 ?；string 等引用类型只有勾选「可空引用类型」时才加 ?。Columns without NOT NULL (and not primary keys) become nullable. Value types always get ?; reference types like string get ? only when "Nullable reference types" is checked.

「SQL 建表语句转 C# 实体类」免费吗？数据会上传吗？Is the SQL CREATE TABLE to C# Class free? Is my data uploaded?

「SQL 建表语句转 C# 实体类」完全免费，无需注册或安装，手机和电脑都能用；所有处理都在你的浏览器本地完成，输入的内容和文件不会上传到服务器。The SQL CREATE TABLE to C# Class is completely free with no sign-up or install and works on phones and desktops; everything runs locally in your browser and nothing you enter is uploaded.