Python psycopg2转义字符
我有一个postgres查询,如下所示,并在psql上运行find:Python psycopg2转义字符,python,postgresql,psycopg2,Python,Postgresql,Psycopg2,我有一个postgres查询,如下所示,并在psql上运行find: select gcaseid, count (*) as N, array_agg(distinct nvchquestion) as questions, array_agg(nvchanswer) as answers from case_script, case_script_answer w
select
gcaseid,
count (*) as N,
array_agg(distinct nvchquestion) as questions,
array_agg(nvchanswer) as answers
from
case_script,
case_script_answer
where
case_script.gscriptid = case_script_answer.gscriptid and
nvchquestion ilike '%blood pressure%'
group by
gcaseid
order by
N desc
;
现在,我想用Python实现一个类似的查询,这就是我想到的:
import psycopg2
def getAnswers(question):
query = '''
select
gcaseid,
count (*) as N,
array_agg(distinct nvchquestion) as questions,
array_agg(nvchanswer) as answers
from
case_script,
case_script_answer
where
case_script.gscriptid = case_script_answer.gscriptid and
nvchquestion ilike %s
group by
gcaseid
order by
N desc
;
'''%(r"'%%s%'")
conn = psycopg2.connect("dbname='sos' user='postgres' host='localhost'")
cur = conn.cursor()
cur.mogrify(query, (question,))
# cur.execute(query, (question,))
# result = cur.fetchall()
cur.close()
conn.close()
return result
if __name__ == '__main__':
print getAnswers('blood pressure')
print 'done'
现在,当我运行此查询时,我得到了错误:
$ python updateTable.py
Traceback (most recent call last):
File "updateTable.py", line 39, in <module>
print getAnswers('blood pressure')
File "updateTable.py", line 27, in getAnswers
cur.mogrify(query, (question,))
ValueError: unsupported format character ''' (0x27) at index 442
$python updateTable.py
回溯(最近一次呼叫最后一次):
文件“updateTable.py”,第39行,在
打印getAnswers(“血压”)
getAnswers中第27行的文件“updateTable.py”
cur.mogrify(查询,(问题)
ValueError:索引442处不支持的格式字符“”(0x27)
不知道发生了什么。任何人都可以澄清吗?请在查询中使用
%%
来表示类似的野生字符:
execute(" ... ilike %%%s%%", [question])
或者在您的值中用%
s环绕您的值:
execute(" ... ilike %s", ['%' + question + '%']
请参阅查询中的。使用%%
来表示类似于的:
execute(" ... ilike %%%s%%", [question])
或者在您的值中用%
s环绕您的值:
execute(" ... ilike %s", ['%' + question + '%']
请参阅。传递连接到参数的%
的最简单方法,建议如下:
输出:
select 'x' ilike '%x%'
True
select 'x' ilike format('%%%1$s%%', 'x')
True
但是,如果要保持参数干净,请使用格式
:
query = "select 'x' ilike format('%%%%%%1$s%%%%', %s)"
print (cursor.mogrify(query, ('x',)).decode('utf8'))
cursor.execute(query, ('x',))
print (cursor.fetchone()[0])
输出:
select 'x' ilike '%x%'
True
select 'x' ilike format('%%%1$s%%', 'x')
True
最简单的方法是按照以下建议将连接到参数的%
传递到参数:
输出:
select 'x' ilike '%x%'
True
select 'x' ilike format('%%%1$s%%', 'x')
True
但是,如果要保持参数干净,请使用格式
:
query = "select 'x' ilike format('%%%%%%1$s%%%%', %s)"
print (cursor.mogrify(query, ('x',)).decode('utf8'))
cursor.execute(query, ('x',))
print (cursor.fetchone()[0])
输出:
select 'x' ilike '%x%'
True
select 'x' ilike format('%%%1$s%%', 'x')
True
谢谢这就是我最后使用的!谢谢这就是我最后使用的!