Download an Oracle Table to a CSV File

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__author__ = 'jheaton'
import codecs
import csv
import cx_Oracle
ORACLE_CONNECT = "schema/password@(DESCRIPTION=(SOURCE_ROUTE=OFF)(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=host)(PORT=1532)))(CONNECT_DATA=(SID=STLPESP)(SRVR=sid)))"
OUTPUT_ENCODING = "utf-8"
BATCH_SIZE = 100000
ORACLE_SQL = """
select * from mytable
"""
def append_row(filename,rows):
with codecs.open(filename, "a", OUTPUT_ENCODING) as outfile:
output = csv.writer(outfile, dialect='excel')
for row in rows:
output.writerow(row)
def export_table_data(orcl,filename):
# output each table content to a separate CSV file
with codecs.open(filename, "w", OUTPUT_ENCODING) as infile:
pass
sql = ORACLE_SQL
curs2 = orcl.cursor()
curs2.execute(sql)
cols = []
for col in curs2.description:
cols.append(col[0])
append_row(filename, [cols] )
row = 0
done = False
while not done: # add table rows
row_data = curs2.fetchmany(BATCH_SIZE)
if len(row_data)<1:
done = True
else:
append_row(filename, row_data)
row+=len(row_data)
print("{:,d}".format(row))
orcl = cx_Oracle.connect(ORACLE_CONNECT)
print("Connected to Oracle: " + orcl.version)
export_table_data(orcl,"output.csv")