mdb_schema: Generate Schema DDL or Column Types

In mdbr: Work with Microsoft Access Files

Generate Schema DDL or Column Types

Description

mdb-schema is a utility program distributed with MDB Tools. It produces DDL (data definition language) output for the given database, which can be passed to another database to recreate the Access table structure. With mode = "legacy" (the default), it returns a readr col spec for the table instead.

Usage

mdb_schema(
  path,
  table = NULL,
  mode = c("legacy", "ddl"),
  condense = FALSE,
  namespace = NULL,
  backend = c("access", "sybase", "oracle", "postgres", "mysql", "sqlite"),
  drop_table = FALSE,
  not_null = TRUE,
  default_values = FALSE,
  not_empty = FALSE,
  comments = TRUE,
  indexes = TRUE,
  relations = TRUE,
  as_list = TRUE
)

Arguments

path	Path to .mdb/.accdb file.
table	Table name(s). For mode = "ddl", defaults to all user tables. For mode = "legacy", exactly one table name must be given.
mode	"legacy" (default) returns a readr::cols() specification, matching the k5cents/mdbr canonical API. Requires the readr package. "ddl" returns DDL text.
condense	Logical; only used when mode = "legacy". When TRUE, passes the col spec through readr::cols_condense(). Default FALSE.
namespace	Prefix identifiers with namespace, equivalent to -N/--namespace. Only used when mode = "ddl".
backend	Target DDL dialect. Supported values are access, sybase, oracle, postgres, mysql, and sqlite. Only used when mode = "ddl".
drop_table	Issue ⁠DROP TABLE⁠ statements.
not_null	Include ⁠NOT NULL⁠ constraints.
default_values	Include DEFAULT values.
not_empty	Include ⁠CHECK <> ''⁠ constraints.
comments	Include ⁠COMMENT ON⁠ statements.
indexes	Export indexes.
relations	Request foreign key constraints. Current library-mode implementation emits a placeholder comment; full FK export is not yet implemented.
as_list	Logical; defaults to TRUE. When TRUE, returns a named mdblist of DDL text entries keyed by table name. Only used when mode = "ddl".

Value

When mode = "legacy", a readr::cols() specification (optionally condensed via readr::cols_condense()). Requires the readr package. When mode = "ddl" and as_list = TRUE, a named mdblist of table-level DDL text.

Examples

db <- mdbr:::.mdb_example_nwind_path()
if (nzchar(db)) {
  mdb_schema(db, table = "Products")
  mdb_schema(db, table = "Products", mode = "ddl")
}

mdbr documentation built on May 28, 2026, 5:09 p.m.