`sqlgen::write`

The sqlgen::write interface provides a type-safe way to write data from C++ containers or ranges to a SQL database. It handles table creation, batch processing, and error handling automatically.

Usage

Basic Write

Write a container of objects to a database:

const auto people = std::vector<Person>({
    Person{.id = 0, .first_name = "Homer", .last_name = "Simpson", .age = 45},
    Person{.id = 1, .first_name = "Bart", .last_name = "Simpson", .age = 10}
});

// Using with a connection reference
const auto conn = sqlgen::sqlite::connect();
sqlgen::write(conn, people);

With Result<Ref>

Handle connection creation and writing in a single chain:

sqlgen::sqlite::connect("database.db")
    .and_then([&](auto&& conn) { return sqlgen::write(conn, people); })
    .value();

With Iterators

Write a range of objects using iterators:

std::vector<Person> people = /* ... */;
sqlgen::write(conn, people.begin(), people.end());

How It Works

The write function performs the following operations in sequence:

Creates a table if it doesn't exist (using the object's structure)
Prepares an insert statement
Writes the data in batches of SQLGEN_BATCH_SIZE, which you can set at compile time
Handles any errors that occur during the process

Notes

The function automatically creates the table, if it doesn't exist
Data is written in batches for better performance
The Result<Nothing> type provides error handling; use .value() to extract the result (will throw an exception if there's an error) or handle errors as needed
The function has three overloads:
1. Takes a connection reference and iterators
2. Takes a Result<Ref<Connection>> and iterators
3. Takes a connection and a container directly

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sqlgen::write