sqlgen Documentation

Welcome to the sqlgen documentation. This guide provides detailed information about sqlgen’s features and APIs.

Core Concepts

How to install sqlgen.

Defining Tables

How to define tables using C++ structs.

How to represent columns in queries.

sqlgen::literals

How to use column and table alias literals in queries.

sqlgen::Flatten

How to "inherit" fields from other structs.

sqlgen::PrimaryKey

How to define primary keys in sqlgen.

How sqlgen handles errors and results.

How to transpile C++ operations to dialect-specific SQL.

Database I/O

How to read data from a database.

How to write data to a database.

Database Operations

sqlgen::create_as

How to create tables and views from SELECT queries.

sqlgen::create_index

How to create an index on a table.

sqlgen::create_table

How to create a new table.

sqlgen::delete_from

How to delete data from a table.

How to drop a table.

How to execute raw SQL statements.

sqlgen::group_by and Aggregations

How to generate GROUP BY queries and aggregate data.

sqlgen::inner_join, left_join, right_join, full_join

How to join different tables.

sqlgen::insert, insert_or_replace

How to insert data within transactions.

sqlgen::select_from

How to read data from a database using more complex queries.

sqlgen::unite and unite_all

How to combine results from multiple SELECT statements.

How to update data in a table.

Other Operations

How to improve performance with caching.

Mathematical Operations

How to use mathematical functions in queries (e.g., abs, ceil, floor, exp, trigonometric functions, round).

String Operations

How to manipulate and transform strings in queries (e.g., length, lower, upper, trim, replace, concat).

Type Conversion Operations

How to convert between types safely in queries (e.g., cast int to double).

Null Handling Operations

How to handle nullable values and propagate nullability correctly (e.g., with coalesce and nullability rules).

Timestamp and Date/Time Functions

How to work with timestamps, dates, and times (e.g., extract parts, perform arithmetic, convert formats).

How to work with enums in sqlgen.

Data Types and Validation

sqlgen::Dynamic

How to define custom SQL types not natively supported by sqlgen.

sqlgen::ForeignKey

How to establish referential integrity between tables.

How to store and work with JSON fields.

sqlgen::Pattern

How to add regex pattern validation to avoid SQL injection.

sqlgen::Timestamp

How timestamps work in sqlgen.

How to enforce uniqueness constraints on table columns.

sqlgen::Varchar

How varchars work in sqlgen.

Other concepts

Connection Pool

How to manage database connections efficiently.

How to use transactions for atomic operations.

How to create and manage database views.

Supported Databases

How to interact with DuckDB.

How to interact with MariaDB and MySQL.

How to interact with PostgreSQL and compatible databases (Redshift, Aurora, Greenplum, CockroachDB, …).

How to interact with SQLite3.

For installation instructions, quick start guide, and usage examples, please refer to the main README.