2.1. duckdb_provider — SqlProviderInfo registration shim

DuckDB’s entry in the neutral SQL provider registry (daslib/sql_provider) — the compile-time half of the provider. register_duckdb_provider is called by sql_register_present_providers (from daslib/sql_boost) in every macro context that analyzes _sql chains; the entry carries the DuckStmt? statement-type factories the macros splice into emitted bind/reader blocks, the dialect hooks (? placeholders, json_extract_string for @sql_json descent — DuckDB’s plain json_extract returns a typed JSON value that breaks VARCHAR comparisons — and the BIGINT / DOUBLE / VARCHAR type spellings), and the capability flags (client UDFs and RETURNING on; FTS5 off — DuckDB’s full-text extension is a different surface).

The runtime helpers here (duckdb_read_table_info, the read-only schema_from reader, duckdb_sql_type / duckdb_decl_to_sql_type) back check_schema and [sql_table(schema_from=...)]. This module deliberately does not require duckdb/duckdb_boost — that would cycle through daslib/sql_boost.

2.1.1. Registration

register_duckdb_provider()

def register_duckdb_provider ()

2.1.2. Dialect helpers

duckdb_decl_to_sql_type(decl_type: string ): SqlType

def duckdb_decl_to_sql_type (decl_type: string) : SqlType

Arguments:

  • decl_type : string

duckdb_sql_type(t: SqlType ): string

def duckdb_sql_type (t: SqlType) : string

Arguments:

2.1.3. Schema introspection

duckdb_read_table_info(conn: duckdb_connection; schema_name: string; tbl_name: string ): tuple<_is_ok:bool;_value:array<SchemaFromCol>;_error:string>

def duckdb_read_table_info (conn: duckdb_connection; schema_name: string; tbl_name: string) : tuple<_is_ok:bool;_value:array<SchemaFromCol>;_error:string>

Arguments: