C++类型安全SQL模版库：sqlpp11
sqlpp11 是 C++ 的类型安全 SQL 模版库。
sqlpp11 是一个嵌入式领域特定语言（EDSL）的代表模版库：
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为表和列定义类型
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在编译的时候检查结构类型安全查询（语法错误，类型错误，命名错误，甚至是一些语义错误）
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通过迭代 query-specific 结构得到解析结果
示例
CREATE TABLE foo ( id bigint, name varchar(50), hasFun bool );假设有个数据库连接对象：
TabFoo foo; Db db(/* some arguments*/); // selecting zero or more results, iterating over the results for (const auto& row : db(select(foo.name, foo.hasFun).from(foo).where(foo.id > 17 and foo.name.like("%bar%")))) { if (row.name.is_null()) std::cerr << "name is null, will convert to empty string" << std::endl; std::string name = row.name; // string-like fields are implicitly convertible to string bool hasFun = row.hasFun; // bool fields are implicitly convertible to bool } // selecting ALL columns of a table for (const auto& row : db(select(all_of(foo)).from(foo).where(foo.hasFun or foo.name == "joker"))) { int64_t id = row.id; // numeric fields are implicitly convertible to numeric c++ types } // selecting zero or one row, showing off with an alias: SQLPP_ALIAS_PROVIDER(cheese); if (const auto& row = db(select(foo.name.as(cheese)).from(foo).where(foo.id == 17))) { std::cerr << "found: " << row.cheese << std::endl; } // selecting a single row with a single result: return db(select(count(foo.id)).from(foo).where(true)).front().count; Of course there are joins and subqueries, more functions, order_by, group_by etc. These will be documented soon. // A sample insert db(insert_into(foo).set(foo.id = 17, foo.name = "bar", foo.hasFun = true)); // A sample update db(update(foo).set(foo.hasFun = not foo.hasFun).where(foo.name != "nobody")); // A sample delete db(remove_from(foo).where(not foo.hasFun));
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