Explain Plan for queries

Hi, I have a bunch of issues, though mostly related to obtaining the query plan in informix. I am working with version 9.30. I am a newbie to Informix online dynamic server. So my questions might be too basic. Please be patient with me. I need to obtain the query plan for a set of queries and tune them. I am using DBACCESS to run the queries. Going through the documents I came to know that I can get the query plan by executing SET EXPLAIN ON and then executing my queries. Now I have the following questions 1. Is there a way in INFORMIX as in ORACLE to obtain the query plan, without actually executing the queries? If yes how? 2. As I mentioned I need to obtain query plans for multiple queries. Is there a way to run a whole file having all these queries using DBACCESS? 3. All my queries are huge in size. So is there a mechanism to set the SQL Edit buffer size in dbaccess, as I am getting a error "801: SQL Edit buffer is full." 4. As in Oracle SQLPLUS (set spool on), is there a way to redirect the output to a file in Informix. Please clarify -- Posted via http://dbforums.com

ovkrishna wrote: > I have a bunch of issues, though mostly related to obtaining the query > plan in informix. I am working with version 9.30. > > I am a newbie to Informix online dynamic server. So my questions might > be too basic. Please be patient with me. > > I need to obtain the query plan for a set of queries and tune them. I am > using DBACCESS to run the queries. Going through the documents I came to > know that I can get the query plan by executing SET EXPLAIN ON and then > executing my queries. Now I have the following questions > > 1. Is there a way in INFORMIX as in ORACLE to obtain the query plan, > without actually executing the queries? If yes how? Not in 9.30, I think there is an EXPLAIN optimiser directive in 9.40. > 2. As I mentioned I need to obtain query plans for multiple > queries. Is there a way to run a whole file having all these > queries using DBACCESS? Yes. Edit a file to contain: SET EXPLAIN ON;SELECT ...; SELECT ...; SELECT ...; Then execute "dbaccess yourdatabase yourfile" -- this should leave all the explain plans in sqexplain.out. > 3. All my queries are huge in size. So is there a mechanism to set the > SQL Edit buffer size in dbaccess, as I am getting a error "801: SQL > Edit buffer is full." Run them from the command line. > 4. As in Oracle SQLPLUS (set spool on), is there a way to redirect the > output to a file in Informix. OUTPUT TO "filename" SELECT ...; -- Ciao, The Obnoxious One "Ogni uomo mi guarda come se fossi una testa di cazzo"