hi,Bruce Momjian

	I think you are wrong. multiple query in a string, such as ""SELECT;SELECT" will invoke pg_execute_query_string twice, It won't generate two parsetree.
	

======= 2003-03-26 10:20:00 您在来信中写道：=======

>Jinqiang Han wrote:
>> hello,
>>
>> I have read the source code of postgres.c. Two strang things I can't understand.
>> Souce code of Postgres.c:
>> ..
>> Foreach(parsetree_list的元素parsetree){ //In what situation here will be many parsetrees？
>> …
>
>You can send multiple queries in a single string, "SELECT;SELECT".
>
>> (List *)querytree_list = pg_analyze_and_rewrite(parsetree);
>> 	foreach(querytree_list中的每个querytree){ //In what situation here will be many querytrees？
>
>A RULE may have additional queries to fire.
>
>>
>> Who can tell me the reason?
>> Thank you very much
>>
>> Jinqiang Han
>>
>>
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>
>--
>  Bruce Momjian                        |  http://candle.pha.pa.us
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Thu, 27 Mar 2003 10:21:53 +0800
"Jinqiang Han" <postgresql@db.pku.edu.cn>
Re: inquiry
"Jinqiang Han" <postgresql@db.pku.edu.cn> writes:
> hi,Bruce Momjian
> 	I think you are wrong. multiple query in a string, such as ""SELECT;SELECT" will invoke pg_execute_query_string twice, It won't generate two parsetree.

Try it in something other than psql.  psql splits such a string into
multiple submissions to the backend --- but other interfaces don't.

			regards, tom lane


Thu, 27 Mar 2003 09:53:00 -0500
Tom Lane <tgl@sss.pgh.pa.us>
Re: inquiry 