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Date: Thu, 12 Dec 2013 15:40:05 -0500
Subject: Code suggestion - List comprehension
From: Shyam Parimal Katti <spk265@nyu.edu>
To: python-list@python.org
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Hello,

I have a list of sql queries, some which are split across multiple list
elements e.x.
['drop table sample_table;', 'create table sample_test', '(col1 int);',
'select col1 from', ' sample_test;']

A semi-colon in the string value  indicates the termination of a sql query.
So the expected out come is a conversion to a list of valid sql queries:
['drop table sample_table;', 'create table sample_test (col1 int);',
'select col1 from sample_test;']

Here is the code that does that:

sample = ['drop table sample_table;', 'create table sample_test', '(col1
int);', 'select col1 from', ' sample_test;']
pure_sqls = []
query_holder= ''
for each_line in sample:
    query_holder += each_line
    if query_holder.endswith(';'):
        pure_sqls.append(query_holder)
        query_holder = ''


Is there a way to do this by eliminating explicit creation of new
list(pure_sqls) and a temporary variable(query_holder)? Using list
comprehension? Though I don't want to put the shorter version in
production(if it is difficult to understand), I am looking if this can be
done with list comprehension since I am trying to learn list comprehension
by using it in such scenarios.

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<div dir=3D"ltr"><div>Hello,</div><div><br></div><div>I have a list of sql =
queries, some which are split across multiple list elements e.x.</div><div>=
[&#39;drop table sample_table;&#39;, &#39;create table sample_test&#39;, &#=
39;(col1 int);&#39;, &#39;select col1 from&#39;, &#39; sample_test;&#39;]</=
div>
<div><br></div><div>A semi-colon in the string value =A0indicates the termi=
nation of a sql query. So the expected out come is a conversion to a list o=
f valid sql queries:</div><div>[&#39;drop table sample_table;&#39;, &#39;cr=
eate table sample_test (col1 int);&#39;, &#39;select col1 from sample_test;=
&#39;]</div>
<div><br></div><div>Here is the code that does that:</div><div><br></div><d=
iv>sample =3D [&#39;drop table sample_table;&#39;, &#39;create table sample=
_test&#39;, &#39;(col1 int);&#39;, &#39;select col1 from&#39;, &#39; sample=
_test;&#39;]</div>
<div>pure_sqls =3D []</div><div>query_holder=3D &#39;&#39;</div><div>for ea=
ch_line in sample:</div><div>=A0 =A0 query_holder +=3D each_line</div><div>=
=A0 =A0 if query_holder.endswith(&#39;;&#39;):</div><div>=A0 =A0 =A0 =A0 pu=
re_sqls.append(query_holder)</div>
<div>=A0 =A0 =A0 =A0 query_holder =3D &#39;&#39;</div><div><br></div><div><=
br></div><div>Is there a way to do this by eliminating explicit creation of=
 new list(pure_sqls) and a temporary variable(query_holder)? Using list com=
prehension? Though I don&#39;t want to put the shorter version in productio=
n(if it is difficult to understand), I am looking if this can be done with =
list comprehension since I am trying to learn list comprehension by using i=
t in such scenarios.</div>
</div>

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