Postgres-XC tutorial PDF - PGCon

Querying distributed table
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Example: simple SELECT on distributed table
CREATE TABLE tab1 (val int, val2 int)
DISTRIBUTE BY HASH(val)
TO NODE datanode_1, datanode_2, datanode_3; ­­ distributed table
EXPLAIN VERBOSE SELECT * FROM tab1 WHERE val2 = 5;
QUERY PLAN
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Data Node Scan on "__REMOTE_FQS_QUERY__"
­­ Gathers rows from the nodes where table is distributed
Output: tab1.val, tab1.val2
Node/s: datanode_1, datanode_2, datanode_3
Remote query: SELECT val, val2 FROM tab1 WHERE (val2 = 5)
May 16th, 2012 Postgres­XC 52