On Mon, Feb 23, 2009 at 5:27 PM, Gregory Stark <st...@enterprisedb.com>wrote:
> Farhan Husain <russ...@gmail.com> writes: > > > I can provide any other information needed and also the data if anyone > > wants. > > What did the query plans look like in both databases? > > In Postgres you can get the query plan with > > EXPLAIN ANALYZE select ... > > You can leave out the ANALYZE if you can't wait until the query completes > but > it will have much less information to diagnosis any problems. > > -- > Gregory Stark > EnterpriseDB http://www.enterprisedb.com > Ask me about EnterpriseDB's Slony Replication support! > Here is what I got from MySQL: mysql> explain Select A0.Subj, A2.Obj From jena_g1t1_stmt A0, jena_g1t1_stmt A1, jena_g1t1_stmt A2 Where A0.Prop='Uv:: http://prismstandard.org/namespaces/1.2/basic/isPartOf:' AND A0.Obj='Uv:: http://ww w.utdallas.edu/~farhan.husain/IngentaConnect/issue1_1:' AND A0.GraphID=1 AND A0.Subj=A1.Subj AND A1.Prop='Uv:: http://www.w3.org/1999/02/22-rdf-syntax-ns#type:' AND A1.Obj='Uv:: http://metastore.ingenta .com/ns/structure/Article:' AND A1.GraphID=1 AND A0.Subj=A2.Subj AND A2.Prop='Uv::http://prismstandard.org/namespaces/1.2/basic/startingPage:' AND A2.GraphID=1; +----+-------------+-------+------+------------------------------------+-------------------+---------+-------------------------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+------------------------------------+-------------------+---------+-------------------------+------+-------------+ | 1 | SIMPLE | A0 | ref | jena_g1t1_stmtXSP,jena_g1t1_stmtXO | jena_g1t1_stmtXO | 102 | const | 628 | Using where | | 1 | SIMPLE | A1 | ref | jena_g1t1_stmtXSP,jena_g1t1_stmtXO | jena_g1t1_stmtXSP | 204 | ingentadb.A0.Subj,const | 1 | Using where | | 1 | SIMPLE | A2 | ref | jena_g1t1_stmtXSP | jena_g1t1_stmtXSP | 204 | ingentadb.A0.Subj,const | 1 | Using where | +----+-------------+-------+------+------------------------------------+-------------------+---------+-------------------------+------+-------------+ 3 rows in set (0.00 sec) -- Mohammad Farhan Husain Research Assistant Department of Computer Science Erik Jonsson School of Engineering and Computer Science University of Texas at Dallas
