Backend

Contents

Backend#

The backend manages the database connection and schema manipulation.

trytond.backend.name#

The name of the backend configured.

Database#

class trytond.backend.Database(name)#

Manage the connection to the named database.

Database.connect()#

Connect to the database and return the instance.

Database.get_connection([autocommit[, readonly]])#

Retrieve a connection object as defined by PEP 249#connection. If autocommit is set, the connection is committed after each statement. If readonly is set, the connection is read only.

Database.put_connection(connection[, close])#

Release the connection. If close is set, the connection is discarded.

Database.close()#

Close all connections.

classmethod Database.create(connection, database_name)#

Create the named database using the connection.

classmethod Database.drop(connection, database_name)#

Drop the named database using the connection.

Database.list([hostname])#

Return a list of Tryton database names. hostname filters the databases with the same configured hostname.

Database.init()#

Initialize the database schema.

Database.test([hostname])#

Return if the database is a Tryton database. If hostname is set, it checks also if it has the same configured hostname.

Database.nextid(connection, table[, count])#

Return the next count IDs for the table using the connection.

Note

It may return None for some database.

Database.setnextid(connection, table, value)#

Set the value as current ID to the table using the connection.

Database.currid(connection, table)#

Return the current ID of the table using the connection.

classmethod Database.lock(connection, table)#

Lock the table using the connection.

Database.lock_id(id[, timeout])#

Return the SQL expression to lock the id. Set timeout to wait for the lock.

Database.has_constraint(constraint)#

Return if the database handle the constraint.

Database.has_returning()#

Return if the database supports RETURNING in INSERT and UPDATE.

Database.has_multirow_insert()#

Return if the database supports INSERT of multi-rows.

Database.has_select_for()#

Return if the database supports FOR UPDATE and FOR SHARE in SELECT.

Database.get_select_for_skip_locked()#

Return For class with skip locked.

Database.has_window_functions()#

Return if the database supports window functions.

Database.has_unaccent()#

Return if the database suppport unaccentuated function.

Database.has_unaccent_indexable()#

Return if the database suppport unaccentuated function in index.

Database.unaccent(value)#

Return the SQL expression of unaccentuated value.

Database.has_similarity()#

Return if the database suppports similarity function.

Database.similarity(column, value)#

Return the SQL expression that compare the similarity of column and value.

Database.has_search_full_text()#

Return if the database suppports full text search.

Database.format_full_text(\*documents[, language])#

Return the SQL expression that format the documents into text search vectors for the language.

The order of documents define the weight for proximity ranking.

Database.format_full_text_query(query[, language])#

Convert the query expression into full text query.

Database.search_full_text(document, query)#

Return the SQL expression for searching document with the query.

Database.rank_full_text(document, query[, normalize])#

Return the SQL expression to rank document with the query.

classmethod Database.has_sequence()#

Return if the database supports sequence querying and assignation.

Database.sequence_exist(connection, name)#

Return if the named sequence exists using the connection.

Database.sequence_create(connection, name[, number_increment[, start_value]])#

Create a named sequence incremented by number_increment or 1 and starting at start_value or 1 using the connection.

Database.sequence_update(connection, name[, number_increment[, start_value]])#

Modify the named sequence with number_increment and start_value using the connection.

Database.sequence_rename(connection, old_name, new_name)#

Rename the sequece from old_name to new_name using the connection.

Database.sequence_delete(connection, name)#

Delete the named sequence using the connection.

Database.sequence_next_number(connection, name)#

Return the next number fo the named sequence using the connection.

Database.has_channel(connection, name)#

Return if the database supports LISTEN and NOTIFY on channel.

Database.sql_type(type_)#

Return the namedtuple(‘SQLType’, ‘base type’) corresponding to the SQL type_.

Database.sql_format(type_, value)#

Return the value casted for the SQL type_.

Database.json_get(column[, key])#

Return the JSON value of the JSON key from the column.

Database.json_key_exists(column, key)#

Return the SQL expression to test if key exists in the JSON column.

Database.json_any_keys_exist(column, keys)#

Return the SQL expression to test if any keys exist in the JSON column.

Database.json_all_keys_exist(column, keys)#

Return the SQL expression to test if all keys exist in the JSON column.

Database.json_contains(column, json)#

Rteurn the SQL expression to test if the JSON column contains json.

TableHandler#

class trytond.backend.TableHandler(model[, history])#

Handle table for the model. If history is set, the table is the one storing the history.

TableHandler.namedatalen#

The maximing length of named data for the database.

TableHandler.index_translators#

Contain the IndexTranslator for the database.

classmethod TableHandler.table_exist(table_name)#

Return if the named table exists.

classmethod TableHandler.table_rename(old_name, new_name)#

Rename the table from old_name to new_name.

TableHandler.column_exist(column_name)#

Return if the named column exists.

TableHandler.column_rename(old_name, new_name)#

Rename the column from old_name to new_name.

TableHandler.alter_size(column_name, column_type)#

Modify the size of the named column using the column type.

TableHandler.alter_type(column_name, column_type)#

Modify the type of the named column.

TableHandler.column_is_type(column_name, type_[, size])#

Return if the column is of type type_. If type is VARCHAR, size is also compared except if the value if negative.

TableHandler.db_default(column_name, value)#

Set the default value on the named column.

TableHandler.add_column(column_name, abstract_type[, default[, comment]])#

Add the named column of abstract type. The default is a method that return the value to fill the new column. comment set as comment for the column.

TableHandler.add_fk(column_name, reference[, on_delete])#

Add a foreign key constraint on the named column to target the reference table name. on_delete defines the method to use when foreign record is deleted.

TableHandler.drop_fk(column_name[, table])#

Drop the foreign key constrant on the named column. table can be used to alter another table.

TableHandler.not_null_action(column_name[, action])#

Add or remove NOT NULL on the named column.

TableHandler.add_constraint(ident, constraint)#

Add the SQL expression constraint as constraint named ident on the table.

TableHandler.drop_constraint(ident[, table])#

Drop the named ident constraint. table can be used to alter another table.

TableHandler.set_indexes(indexes[, concurrently])#

Create the indexes if possible and drop others having idx_ as prefix or _index as suffix.

If concurrently is set indexes are created concurrently if possible. It defaults to False.

TableHandler.drop_column(column_name)#

Drop the named column.

classmethod TableHandler.drop_table(model, table[, cascade])#

Drop the named table and clean ir.model.data from the given model. Set cascade to drop objects that depend on the table.

classmethod TableHandler.convert_name(name[, reserved])#

Convert the data name to be lower than namedatalen minus reserved.

Database.index_translator_for(index)#

Return the best IndexTranslator for the given index.

IndexTranslator#

class trytond.backend.IndexTranslator#

Convert an Index into a concrete index.

classmethod IndexTranslator.definition(index)#

Return the name, SQL query and parameters to create the index.

classmethod IndexTranslator.score(index)#

Return a score related to the fitness of using this translator for the index. A score of 0 means that the translator is unsuited for the requested usage.

Exceptions#

exception trytond.backend.DatabaseIntegrityError#

Exception raised when the relational integrity of the database is affected.

exception trytond.backend.DatabaseDataError#

Exception raised for errors that are due to problems with the processed data.

exception trytond.backend.DatabaseOperationalError#

Exception raised for errors that are related to the database’s operation.