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Class Reference

PyDBML classes represent database entities. They live in the pydbml.classes package.

>>> from pydbml.classes import Table, Column, Reference

The Database class represents a PyDBML database. You can import it from the pydbml package.

>>> from pydbml import Database

Database

Database is the main class, representing a PyDBML database. When PyDBML parses a .dbml file, it returns a Database object. This object holds all objects of the database and makes sure they are properly connected. You can access the Database object by calling the database property of each class (except child classes like Column or Index).

When you are creating PyDBML schema from scratch, you have to add each created object to the database by calling Database.add.

Database object may act as a list or a dictionary of tables:

>>> from pydbml import PyDBML
>>> db = PyDBML.parse_file('test_schema.dbml')
>>> table = db.tables[0]
>>> db['public.orders']
<Table 'public' 'orders'>
>>> db[0]
<Table 'public' 'orders'>

Attributes

  • tables (list of Table) — list of all Table objects, defined in this database.
  • table_dict (dict of Table) — dictionary holding database Table objects. The key is full table name (with schema: public.mytable) or a table alias (myalias).
  • refs (list of Reference) — list of all Reference objects, defined in this database.
  • enums (list of Enum) — list of all Enum objects, defined in this database.
  • table_groups (list of TableGroup) — list of all TableGroup objects, defined in this database.
  • project (Project) — database Project.
  • sql () — SQL definition for this database.
  • dbml () — DBML definition for this table.

Methods

  • add (PyDBML object) — add a PyDBML object to the database.
  • add_table (Table) — add a Table object to the database.
  • add_reference (Reference) — add a Reference object to the database.
  • add_enum (Enum) — add a Enum object to the database.
  • add_table_group (TableGroup) — add a TableGroup object to the database.
  • add_project (Project) — add a Project object to the database.
  • delete (PyDBML object) — delete a PyDBML object from the database.
  • delete_table (Table) — delete a Table object from the database.
  • delete_reference (Reference) — delete a Reference object from the database.
  • delete_enum (Enum) — delete a Enum object from the database.
  • delete_table_group (TableGroup) — delete a TableGroup object from the database.
  • delete_project (Project) — delete a Project object from the database.

Table

Table class represents a database table.

>>> from pydbml import PyDBML
>>> parsed = PyDBML.parse_file('test_schema.dbml')
>>> table = parsed.tables[0]
>>> table
<Table 'public' 'orders'>

Table object may act as a list or a dictionary of columns:

>>> table[0]
<Column 'id', 'int'>
>>> table['status']
<Column 'status', 'orders_status'>

Attributes

  • database (Database) — link to the table's database object, if it was set.
  • name (str) — table name.
  • schema (str) — table schema name.
  • full_name (str) — table name with schema prefix.
  • columns (list of Column) — table columns.
  • indexes (list of Index) — indexes, defined for the table.
  • alias (str) — table alias, if defined.
  • note (str) — note for table, if defined.
  • header_color (str) — the header_color param, if defined.
  • comment (str) — comment, if it was added just before table definition.
  • sql (str) — SQL definition for this table.
  • dbml (str) — DBML definition for this table.

Methods

  • add_column (c: Column) — add a column to the table,
  • delete_column (c: Column or int) — delete a column from the table by Column object or column index.
  • add_index (i: Index) — add an index to the table,
  • delete_index (i: Index or int) — delete an index from the table by Index object or index number.
  • get_refs — get list of references, defined for this table.
  • get_references_for_sql — get list of references where this table is on the left side of FOREIGN KEY definition in SQL.

Column

Column class represents a column of a database table.

Table columns are stored in the columns attribute of a Table object.

Attributes

  • database (Database) — link to the database object of this column's table, if it was set.
  • name (str) — column name,
  • table (Table) — link to Table object, which holds this column.
  • type (str or Enum) — column type. If type is a enum, this attribute will hold a link to corresponding Enum object.
  • unique (bool) — indicates whether the column is unique.
  • not_null (bool) — indicates whether the column is not null.
  • pk (bool) — indicates whether the column is a primary key.
  • autoinc (bool) — indicates whether this is an autoincrement column.
  • default (str or bool or int or float or Expression) — column's default value.
  • note (Note) — column's note if was defined.
  • comment (str) — comment, if it was added just before column definition or right after it on the same line.
  • sql (str) — SQL definition for this column.
  • dbml (str) — DBML definition for this column.

Methods

  • get_refs — get list of references, defined for this column.

Index

Index class represents an index of a database table.

Indexes are stored in the indexes attribute of a Table object.

Attributes

  • subjects (list of Column or Expression) — list subjects which are indexed. Columns are represented by Column objects or Expression objects.
  • subject_names (list of str) — list of index subject names.
  • table (Table) — link to table, for which this index is defined.
  • name (str) — index name, if defined.
  • unique (bool) — indicates whether the index is unique.
  • type (str) — index type, if defined. Can be either hash or btree.
  • pk (bool) — indicates whether this a primary key index.
  • note (note) — index note, if defined.
  • comment (str) — comment, if it was added just before index definition.
  • sql (str) — SQL definition for this index.
  • dbml (str) — DBML definition for this index.

Reference

Reference class represents a database relation.

>>> from pydbml import PyDBML
>>> parsed = PyDBML.parse_file('test_schema.dbml')
>>> parsed.refs[0]
<Reference '<', ['id'], ['order_id']>

Attributes

  • database (Database) — link to the reference's database object, if it was set.
  • type (str) — reference type, in DBML syntax:
    • < — one to many;
    • > — many to one;
    • - — one to one.
  • col1 (list of Column) — list of Column objects of the left side of the reference. Changed in 0.4.0, previously was plain Column.
  • table1 (Table or None) — link to the left Table object of the reference or None of it was not set.
  • col2 (list of Column) — list of Column objects of the right side of the reference. Changed in 0.4.0, previously was plain Column.
  • table2 (Table or None) — link to the right Table object of the reference or None of it was not set.
  • name (str) — reference name, if defined.
  • on_update (str) — reference's on update setting, if defined.
  • on_delete (str) — reference's on delete setting, if defined.
  • comment (str) — comment, if it was added before reference definition.
  • inline (bool) — indicates whether this reference should be rendered inside SQL or DBML definition of the table.
  • sql (str) — SQL definition for this reference.
  • dbml (str) — DBML definition for this reference.

Enum

Enum class represents a enum type in the database.

>>> from pydbml import PyDBML
>>> parsed = PyDBML.parse_file('test_schema.dbml')
>>> enum = parsed.enums[0]
>>> enum
<Enum 'orders_status', ['created', 'running', 'done', 'failure']>

Enum objects also act as a list of items:

>>> enum[0]
<EnumItem 'created'>

Attributes

database name schema comment items

  • database (Database) — link to the enum's database object, if it was set.
  • schema (str) — enum schema name.
  • name (str) — enum name,
  • items (list of EnumItem) — list of items.
  • comment (str) — comment, which was defined before enum definition.
  • sql (str) — SQL definition for this enum.
  • dbml (str) — DBML definition for this enum.

Methods

  • add_item (item: EnumItem or str) — add an item to this enum.

EnumItem

EnumItem class represents an item of a enum type in the database.

Enum items are stored in the items property of a Enum class.

Attributes

  • name (str) — enum item name,
  • note (Note) — enum item note, if was defined.
  • comment (str) — comment, which was defined before enum item definition or right after it on the same line.
  • sql (str) — SQL definition for this enum item.
  • dbml (str) — DBML definition for this enum item.

Note

Note is a basic class, which may appear in some other classes' note attribute. Mainly used for documentation of a DBML database.

Attributes

text (str) — note text.

  • sql (str) — SQL definition for this note.
  • dbml (str) — DBML definition for this note.

Note

new in PyDBML 1.0.10

Sticky notes are similar to regular notes, except that they are defined at the root of your DBML file and have a name.

Attributes

name (str) — note name. text (str) — note text.

  • dbml (str) — DBML definition for this note.

Expression

new in PyDBML 1.0.0

Expression class represents an SQL expression. Expressions may appear in Index subjects or Column default values.

Attributes

text (str) — expression text.

  • sql (str) — SQL definition for this expression.
  • dbml (str) — DBML definition for this expression.

Project

Project class holds DBML project metadata. Project is not present in SQL.

>>> from pydbml import PyDBML
>>> parsed = PyDBML.parse_file('test_schema.dbml')
>>> parsed.project
<Project 'test_schema'>

Attributes

  • database (Database) — link to the project's database object, if it was set.
  • name (str) — project name,
  • items (str) — dictionary with project metadata,
  • note (Note) — note, if was defined,
  • comment (str) — comment, if was added before project definition.
  • dbml (str) — DBML definition for this project.

TableGroup

TableGroup class represents a table group in the DBML database. TableGroups are not present in SQL.

>>> from pydbml import PyDBML
>>> parsed = PyDBML.parse_file('test_schema.dbml')
>>> parsed.table_groups
[<TableGroup 'g1', ['users', 'merchants']>, <TableGroup 'g2', ['countries', 'orders']>]

Attributes

  • database (Database) — link to the tableg group's database object, if it was set.
  • name (str) — table group name,
  • items (str) — dictionary with tables in the group,
  • comment (str) — comment, if was added before table group definition.
  • dbml (str) — DBML definition for this table group.