我想将包含大型 CLOB 的查询结果导出到 CSV 文件。但是，一旦在 CSV 字段中导出，CLOB 会在大约 4K 个字符后被截断(即它们会过早地以“...”结尾)。如何防止 Oracle SQL Developer 在导出时截断 CLOB？
最佳答案
您可以绕过 Oracle SQL Developer 进行导出，例如您可以使用 Python 脚本来处理导出，这样 CLOB 就不会被截断:
from __future__ import print_function
from __future__ import division
import time
import cx_Oracle
def get_cursor():
'''
Get a cursor to the database
'''
# http://stackoverflow.com/questions/24149138/cx-oracle-doesnt-connect-when-using-sid-instead-of-service-name-on-connection-s
# http://www.oracle.com/technetwork/articles/dsl/prez-python-queries-101587.html
ip = '' # E.g. '127.0.0.1'
port = '' # e.g. '3306'
sid = ''
dsnStr = cx_Oracle.makedsn(ip, port, sid)
username = '' # E.g. 'FRANCK'
password = '' # E.g. '123456'
db = cx_Oracle.connect(user=username, password=password, dsn=dsnStr)
cursor = db.cursor()
return cursor
def read_sql(filename):
'''
Read an SQL file and return it as a string
'''
file = open(filename, 'r')
return ' '.join(file.readlines()).replace(';', '')
def execute_sql_file(filename, cursor, verbose = False, display_query = False):
'''
Execute an SQL file and return the results
'''
sql = read_sql(filename)
if display_query: print(sql)
start = time.time()
if verbose: print('SQL query started... ', end='')
cursor.execute(sql)
if verbose:
end = time.time()
print('SQL query done. (took {0} seconds)'.format(end - start))
return cursor
def main():
'''
This is the main function
'''
# Demo:
cursor = oracle_db.get_cursor()
sql_filename = 'your_query.sql' # Write your query there
cursor = oracle_db.execute_sql_file(sql_filename, cursor, True)
result_filename = 'result.csv' # Will export your query result there
result_file = open(result_filename, 'w')
delimiter = ','
for row in cursor:
for count, column in enumerate(row):
if count > 0: result_file.write(delimiter)
result_file.write(str(column))
result_file.write('\n')
result_file.close()
if __name__ == "__main__":
main()
#cProfile.run('main()') # if you want to do some profiling
关于oracle - 防止 Oracle SQL Developer 在导出时截断 CLOB，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/31632983/