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https://issues.apache.org/jira/browse/DERBY-6045?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13650027#comment-13650027
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Mamta A. Satoor commented on DERBY-6045:
----------------------------------------
I tried the new junit delete test case in 10.10 and I see that the test runs
fine on 10.10 without any code changes that went in for this jira. It is
possible that the delete test case does not exactly do what Tony is trying to
do. Tony, thanks for doing the additional testing for a reproducible test case.
I am copying part of the junit test here for easier reference
CREATE TABLE MT_GAF_TOP_LEVEL_TERM_COUNTS (mt BIGINT NOT NULL, term
BIGINT NOT NULL, term_index INTEGER NOT NULL, usage_count BIGINT NOT NULL );
ALTER TABLE MT_GAF_TOP_LEVEL_TERM_COUNTS ADD CONSTRAINT
kb_mt_gaf_top_level_term_counts_pk PRIMARY KEY (mt, term, term_index);
CREATE INDEX kb_mt_gaf_top_level_term_counts_mt_index ON
MT_GAF_TOP_LEVEL_TERM_COUNTS(mt);
CREATE INDEX kb_mt_gaf_top_level_term_counts_term_index ON
MT_GAF_TOP_LEVEL_TERM_COUNTS(term);
Then I insert 10K rows in the table
PreparedStatement ps = s.getConnection().prepareStatement(
"insert into " + DERBY_6045_DATA_TABLE2 +
" VALUES (?, ?, ?, ?)");
int numberOfRows = 10000;
for (int i=1; i<=numberOfRows; i++) {
ps.setInt(1, i);
ps.setInt(2, i);
ps.setInt(3, i);
ps.setInt(4, i);
ps.executeUpdate();
}
Next, I execute following 2 delete statements and check the runtime statistics
for them
if (useParameterMarkers) {
ps = prepareStatement("DELETE FROM MT_GAF_TOP_LEVEL_TERM_COUNTS
WHERE (term = ?) ");
ps.setInt(1,1);
ps.execute();
} else {
s.execute("DELETE FROM MT_GAF_TOP_LEVEL_TERM_COUNTS WHERE (term
= 2) ");
}
rtsp = SQLUtilities.getRuntimeStatisticsParser(s);
assertTrue(rtsp.usedIndexScan());
if (useParameterMarkers) {
ps = prepareStatement("DELETE FROM mt_gaf_top_level_term_counts
WHERE (term = ?) OR (mt = ?)");
ps.setInt(1,3);
ps.setInt(2,4);
ps.execute();
} else {
s.execute("DELETE FROM mt_gaf_top_level_term_counts WHERE (term
= 5) OR (mt = 6)");
}
rtsp = SQLUtilities.getRuntimeStatisticsParser(s);
assertTrue(rtsp.usedIndexScan());
> in list multi-probe by primary key not chosen on tables with >256 rows
> ----------------------------------------------------------------------
>
> Key: DERBY-6045
> URL: https://issues.apache.org/jira/browse/DERBY-6045
> Project: Derby
> Issue Type: Bug
> Components: SQL
> Affects Versions: 10.9.1.0, 10.10.1.1
> Environment: Linux Debian 6.0.5
> Reporter: Tony Brusseau
> Fix For: 10.11.0.0
>
> Attachments: DERBY6045_patch1_diff.txt, DERBY6045_patch2_diff.txt,
> optimizerTraceOutputFor10_8.txt, optimizerTraceOutputForTrunk.txt,
> optimizerTraceOutputWithUpdateStatsFor10_8.txt,
> optimizerTraceOutputWithUpdateStatsForTrunk.txt
>
>
> I have a table with a long integer primary key field and 11 million rows. I
> seem to be unable to load large chunks of rows via id in a reasonably
> efficient manner.
> 1. If I do individual lookups via the primary key, then a fast indexed
> lookup occurs. However, if I do large numbers of such queries, then the time
> is overwhelmed by round-trip overhead which makes everything incredibly slow.
> 2. If I use a single query with a disjunction of the primary keys of
> interest, then a table scan is performed (even if the clause only contains
> 1-3 items), which walks over 11 million rows...incredibly inefficient.
> 3. If I use an IN clause, then a table scan is performed (even if the
> clause only contains 1-3 items), which walks over 11 million
> rows...incredibly inefficient.
> I'm guessing that this might have something to do with the fact that I'm
> using large integers and really big numbers that don't start anywhere at or
> about 1 for my keys. Could this possibly be confusing the optimizer?
> Here are the unlimited query plans for the 3 cases that I enumerated:
> *********************************************************************************************
> [EL Fine]: 2013-01-17
> 11:09:53.384--ServerSession(582235416)--Connection(1430986883)--Thread(Thread["Initial
> Lisp Listener",5,SubL Thread Group])--SELECT TERM_ID, ARG0, ARG1, ARG2,
> ARG3, FORMULA_HASH, FORMULA_LENGTH, FORMULA_TYPE, KB_STATUS FROM
> KB.FORMULA_TERM WHERE (TERM_ID = ?)
> bind => [2251799814033500]
> Thu Jan 17 11:09:53 CST 2013 Thread["Initial Lisp Listener",5,SubL Thread
> Group] (XID = 4711079), (SESSIONID = 3), SELECT TERM_ID, ARG0, ARG1, ARG2,
> ARG3, FORMULA_HASH, FORMULA_LENGTH, FORMULA_TYPE, KB_STATUS FROM
> KB.FORMULA_TERM WHERE (TERM_ID = ?) ******* Project-Restrict ResultSet (3):
> Number of opens = 1
> Rows seen = 1
> Rows filtered = 0
> restriction = false
> projection = true
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> restriction time (milliseconds) = 0
> projection time (milliseconds) = 0
> optimizer estimated row count: 1.00
> optimizer estimated cost: 6.59
> Source result set:
> Index Row to Base Row ResultSet for FORMULA_TERM:
> Number of opens = 1
> Rows seen = 1
> Columns accessed from heap = {1, 2, 3, 4, 5, 6, 7, 8}
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> optimizer estimated row count: 1.00
> optimizer estimated cost: 6.59
> Index Scan ResultSet for FORMULA_TERM using constraint
> KB_FORMULA_TERM_TERM_ID_PK at read committed isolation level using share row
> locking chosen by the optimizer
> Number of opens = 1
> Rows seen = 1
> Rows filtered = 0
> Fetch Size = 1
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> next time in milliseconds/row = 0
> scan information:
> Bit set of columns fetched=All
> Number of columns fetched=2
> Number of deleted rows visited=0
> Number of pages visited=3
> Number of rows qualified=1
> Number of rows visited=1
> Scan type=btree
> Tree height=-1
> start position:
> >= on first 1 column(s).
> Ordered null semantics on the following
> columns:
> stop position:
> > on first 1 column(s).
> Ordered null semantics on the following
> columns:
> qualifiers:
> None
> optimizer estimated row count: 1.00
> optimizer estimated cost: 6.59
> [EL Fine]: 2013-01-17
> 11:01:00.732--ServerSession(1237006689)--Connection(927179828)--Thread(Thread["Initial
> Lisp Listener",5,SubL Thread Group])--SELECT TERM_ID, ARG0, ARG1, ARG2,
> ARG3, FORMULA_HASH, FORMULA_LENGTH, FORMULA_TYPE, KB_STATUS FROM
> KB.FORMULA_TERM WHERE (((TERM_ID = ?) OR (TERM_ID = ?)) OR (TERM_ID = ?))
> bind => [2251799814033500, 2251799814033501, 2251799814033499]
> Thu Jan 17 11:01:10 CST 2013 Thread["Initial Lisp Listener",5,SubL Thread
> Group] (XID = 4711078), (SESSIONID = 3), SELECT TERM_ID, ARG0, ARG1, ARG2,
> ARG3, FORMULA_HASH, FORMULA_LENGTH, FORMULA_TYPE, KB_STATUS FROM
> KB.FORMULA_TERM WHERE (((TERM_ID = ?) OR (TERM_ID = ?)) OR (TERM_ID = ?))
> ******* Project-Restrict ResultSet (3):
> Number of opens = 1
> Rows seen = 3
> Rows filtered = 0
> restriction = false
> projection = true
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> restriction time (milliseconds) = 0
> projection time (milliseconds) = 0
> optimizer estimated row count: 1176730.30
> optimizer estimated cost: 5931065.54
> Source result set:
> Project-Restrict ResultSet (2):
> Number of opens = 1
> Rows seen = 11767298
> Rows filtered = 11767295
> restriction = true
> projection = false
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> restriction time (milliseconds) = 0
> projection time (milliseconds) = 0
> optimizer estimated row count: 1176730.30
> optimizer estimated cost: 5931065.54
> Source result set:
> Table Scan ResultSet for FORMULA_TERM at read committed
> isolation level using instantaneous share row locking chosen by the optimizer
> Number of opens = 1
> Rows seen = 11767298
> Rows filtered = 0
> Fetch Size = 16
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> next time in milliseconds/row = 0
> scan information:
> Bit set of columns fetched=All
> Number of columns fetched=9
> Number of pages visited=34358
> Number of rows qualified=11767298
> Number of rows visited=11767298
> Scan type=heap
> start position:
> null
> stop position:
> null
> qualifiers:
> None
> optimizer estimated row count: 1176730.30
> optimizer estimated cost: 5931065.54
> [EL Fine]: 2013-01-17
> 11:27:00.627--ServerSession(1237006689)--Connection(1688096771)--Thread(Thread["Initial
> Lisp Listener",5,SubL Thread Group])--SELECT TERM_ID, ARG0, ARG1, ARG2,
> ARG3, FORMULA_HASH, FORMULA_LENGTH, FORMULA_TYPE, KB_STATUS FROM
> KB.FORMULA_TERM WHERE (TERM_ID IN (?,?,?))
> bind => [2251799814033500, 2251799814033501, 2251799814033499]
> Thu Jan 17 11:47:26 CST 2013 Thread["Initial Lisp Listener",5,SubL Thread
> Group] (XID = 4711080), (SESSIONID = 3), SELECT TERM_ID, ARG0, ARG1, ARG2,
> ARG3, FORMULA_HASH, FORMULA_LENGTH, FORMULA_TYPE, KB_STATUS FROM
> KB.FORMULA_TERM WHERE (TERM_ID IN (?,?,?)) ******* Project-Restrict ResultSet
> (3):
> Number of opens = 1
> Rows seen = 3
> Rows filtered = 0
> restriction = false
> projection = true
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> restriction time (milliseconds) = 0
> projection time (milliseconds) = 0
> optimizer estimated row count: 1176730.30
> optimizer estimated cost: 5931065.54
> Source result set:
> Project-Restrict ResultSet (2):
> Number of opens = 1
> Rows seen = 11767298
> Rows filtered = 11767295
> restriction = true
> projection = false
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> restriction time (milliseconds) = 0
> projection time (milliseconds) = 0
> optimizer estimated row count: 1176730.30
> optimizer estimated cost: 5931065.54
> Source result set:
> Table Scan ResultSet for FORMULA_TERM at read committed
> isolation level using instantaneous share row locking chosen by the optimizer
> Number of opens = 1
> Rows seen = 11767298
> Rows filtered = 0
> Fetch Size = 16
> constructor time (milliseconds) = 0
> open time (milliseconds) = 0
> next time (milliseconds) = 0
> close time (milliseconds) = 0
> next time in milliseconds/row = 0
> scan information:
> Bit set of columns fetched=All
> Number of columns fetched=9
> Number of pages visited=34358
> Number of rows qualified=11767298
> Number of rows visited=11767298
> Scan type=heap
> start position:
> null
> stop position:
> null
> qualifiers:
> None
> optimizer estimated row count: 1176730.30
> optimizer estimated cost: 5931065.54
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