Source code for airflow.hooks.oracle_hook

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import cx_Oracle

from airflow.hooks.dbapi_hook import DbApiHook
from builtins import str
from past.builtins import basestring
from datetime import datetime
import numpy


[docs]class OracleHook(DbApiHook): """ Interact with Oracle SQL. """
[docs] conn_name_attr = 'oracle_conn_id'
[docs] default_conn_name = 'oracle_default'
[docs] supports_autocommit = False
[docs] def get_conn(self): """ Returns a oracle connection object Optional parameters for using a custom DSN connection (instead of using a server alias from tnsnames.ora) The dsn (data source name) is the TNS entry (from the Oracle names server or tnsnames.ora file) or is a string like the one returned from makedsn(). :param dsn: the host address for the Oracle server :param service_name: the db_unique_name of the database that you are connecting to (CONNECT_DATA part of TNS) You can set these parameters in the extra fields of your connection as in ``{ "dsn":"some.host.address" , "service_name":"some.service.name" }`` see more param detail in `cx_Oracle.connect <https://cx-oracle.readthedocs.io/en/latest/module.html#cx_Oracle.connect>`_ """ conn = self.get_connection(self.oracle_conn_id) conn_config = { 'user': conn.login, 'password': conn.password } dsn = conn.extra_dejson.get('dsn', None) sid = conn.extra_dejson.get('sid', None) mod = conn.extra_dejson.get('module', None) service_name = conn.extra_dejson.get('service_name', None) port = conn.port if conn.port else 1521 if dsn and sid and not service_name: conn_config['dsn'] = cx_Oracle.makedsn(dsn, port, sid) elif dsn and service_name and not sid: conn_config['dsn'] = cx_Oracle.makedsn(dsn, port, service_name=service_name) else: conn_config['dsn'] = conn.host if 'encoding' in conn.extra_dejson: conn_config['encoding'] = conn.extra_dejson.get('encoding') # if `encoding` is specific but `nencoding` is not # `nencoding` should use same values as `encoding` to set encoding, inspired by # https://github.com/oracle/python-cx_Oracle/issues/157#issuecomment-371877993 if 'nencoding' not in conn.extra_dejson: conn_config['nencoding'] = conn.extra_dejson.get('encoding') if 'nencoding' in conn.extra_dejson: conn_config['nencoding'] = conn.extra_dejson.get('nencoding') if 'threaded' in conn.extra_dejson: conn_config['threaded'] = conn.extra_dejson.get('threaded') if 'events' in conn.extra_dejson: conn_config['events'] = conn.extra_dejson.get('events') mode = conn.extra_dejson.get('mode', '').lower() if mode == 'sysdba': conn_config['mode'] = cx_Oracle.SYSDBA elif mode == 'sysasm': conn_config['mode'] = cx_Oracle.SYSASM elif mode == 'sysoper': conn_config['mode'] = cx_Oracle.SYSOPER elif mode == 'sysbkp': conn_config['mode'] = cx_Oracle.SYSBKP elif mode == 'sysdgd': conn_config['mode'] = cx_Oracle.SYSDGD elif mode == 'syskmt': conn_config['mode'] = cx_Oracle.SYSKMT elif mode == 'sysrac': conn_config['mode'] = cx_Oracle.SYSRAC purity = conn.extra_dejson.get('purity', '').lower() if purity == 'new': conn_config['purity'] = cx_Oracle.ATTR_PURITY_NEW elif purity == 'self': conn_config['purity'] = cx_Oracle.ATTR_PURITY_SELF elif purity == 'default': conn_config['purity'] = cx_Oracle.ATTR_PURITY_DEFAULT conn = cx_Oracle.connect(**conn_config) if mod is not None: conn.module = mod return conn
[docs] def insert_rows(self, table, rows, target_fields=None, commit_every=1000): """ A generic way to insert a set of tuples into a table, the whole set of inserts is treated as one transaction Changes from standard DbApiHook implementation: - Oracle SQL queries in cx_Oracle can not be terminated with a semicolon (`;`) - Replace NaN values with NULL using `numpy.nan_to_num` (not using `is_nan()` because of input types error for strings) - Coerce datetime cells to Oracle DATETIME format during insert :param table: target Oracle table, use dot notation to target a specific database :type table: str :param rows: the rows to insert into the table :type rows: iterable of tuples :param target_fields: the names of the columns to fill in the table :type target_fields: iterable of str :param commit_every: the maximum number of rows to insert in one transaction Default 1000, Set greater than 0. Set 1 to insert each row in each single transaction :type commit_every: int """ if target_fields: target_fields = ', '.join(target_fields) target_fields = '({})'.format(target_fields) else: target_fields = '' conn = self.get_conn() cur = conn.cursor() if self.supports_autocommit: cur.execute('SET autocommit = 0') conn.commit() i = 0 for row in rows: i += 1 lst = [] for cell in row: if isinstance(cell, basestring): lst.append("'" + str(cell).replace("'", "''") + "'") elif cell is None: lst.append('NULL') elif type(cell) == float and \ numpy.isnan(cell): # coerce numpy NaN to NULL lst.append('NULL') elif isinstance(cell, numpy.datetime64): lst.append("'" + str(cell) + "'") elif isinstance(cell, datetime): lst.append("to_date('" + cell.strftime('%Y-%m-%d %H:%M:%S') + "','YYYY-MM-DD HH24:MI:SS')") else: lst.append(str(cell)) values = tuple(lst) sql = 'INSERT /*+ APPEND */ ' \ 'INTO {0} {1} VALUES ({2})'.format(table, target_fields, ','.join(values)) cur.execute(sql) if i % commit_every == 0: conn.commit() self.log.info('Loaded %s into %s rows so far', i, table) conn.commit() cur.close() conn.close() self.log.info('Done loading. Loaded a total of %s rows', i)
[docs] def bulk_insert_rows(self, table, rows, target_fields=None, commit_every=5000): """ A performant bulk insert for cx_Oracle that uses prepared statements via `executemany()`. For best performance, pass in `rows` as an iterator. :param table: target Oracle table, use dot notation to target a specific database :type table: str :param rows: the rows to insert into the table :type rows: iterable of tuples :param target_fields: the names of the columns to fill in the table, default None. If None, each rows should have some order as table columns name :type target_fields: iterable of str Or None :param commit_every: the maximum number of rows to insert in one transaction Default 5000. Set greater than 0. Set 1 to insert each row in each transaction :type commit_every: int """ if not rows: raise ValueError("parameter rows could not be None or empty iterable") conn = self.get_conn() cursor = conn.cursor() values_base = target_fields if target_fields else rows[0] prepared_stm = 'insert into {tablename} {columns} values ({values})'.format( tablename=table, columns='({})'.format(', '.join(target_fields)) if target_fields else '', values=', '.join(':%s' % i for i in range(1, len(values_base) + 1)), ) row_count = 0 # Chunk the rows row_chunk = [] for row in rows: row_chunk.append(row) row_count += 1 if row_count % commit_every == 0: cursor.prepare(prepared_stm) cursor.executemany(None, row_chunk) conn.commit() self.log.info('[%s] inserted %s rows', table, row_count) # Empty chunk row_chunk = [] # Commit the leftover chunk cursor.prepare(prepared_stm) cursor.executemany(None, row_chunk) conn.commit() self.log.info('[%s] inserted %s rows', table, row_count) cursor.close() conn.close()

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