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https://issues.apache.org/jira/browse/DERBY-6045?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13557713#comment-13557713
]
Tony Brusseau commented on DERBY-6045:
--------------------------------------
I just tried it with regular integers, starting from 1 and the only indexing
being the primary key. Still get the same issue. If I make a table with 64
rows, then it does fast b-tree scans using the IN query. If the table has 256
or more rows, it does slow heap scans over every row in the table when using
the IN query. It looks like maybe there is a logic-po in the code. Doing full
table scans over small tables might be faster than multi-probing, but instead
it is doing it on large tables. This is just a wild guess.
Here is the SQL:
DROP TABLE VARIABLE_TERM;
CREATE TABLE VARIABLE_TERM
(
term_id INTEGER NOT NULL,
var_name VARCHAR(1024) NOT NULL,
var_type SMALLINT NOT NULL,
kb_status INTEGER NOT NULL
);
ALTER TABLE variable_term ADD CONSTRAINT kb_variable_term_term_id_pk PRIMARY
KEY (term_id);
INSERT INTO VARIABLE_TERM VALUES (1, '?var0', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (2, '?var1', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (3, '?var2', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (4, '?var3', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (5, '?var4', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (6, '?var5', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (7, '?var6', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (8, '?var7', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (9, '?var8', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (10, '?var9', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (11, '?var10', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (12, '?var11', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (13, '?var12', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (14, '?var13', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (15, '?var14', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (16, '?var15', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (17, '?var16', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (18, '?var17', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (19, '?var18', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (20, '?var19', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (21, '?var20', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (22, '?var21', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (23, '?var22', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (24, '?var23', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (25, '?var24', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (26, '?var25', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (27, '?var26', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (28, '?var27', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (29, '?var28', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (30, '?var29', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (31, '?var30', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (32, '?var31', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (33, '?var32', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (34, '?var33', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (35, '?var34', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (36, '?var35', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (37, '?var36', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (38, '?var37', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (39, '?var38', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (40, '?var39', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (41, '?var40', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (42, '?var41', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (43, '?var42', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (44, '?var43', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (45, '?var44', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (46, '?var45', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (47, '?var46', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (48, '?var47', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (49, '?var48', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (50, '?var49', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (51, '?var50', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (52, '?var51', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (53, '?var52', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (54, '?var53', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (55, '?var54', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (56, '?var55', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (57, '?var56', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (58, '?var57', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (59, '?var58', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (60, '?var59', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (61, '?var60', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (62, '?var61', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (63, '?var62', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (64, '?var63', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (65, '?var64', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (66, '?var65', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (67, '?var66', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (68, '?var67', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (69, '?var68', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (70, '?var69', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (71, '?var70', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (72, '?var71', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (73, '?var72', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (74, '?var73', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (75, '?var74', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (76, '?var75', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (77, '?var76', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (78, '?var77', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (79, '?var78', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (80, '?var79', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (81, '?var80', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (82, '?var81', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (83, '?var82', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (84, '?var83', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (85, '?var84', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (86, '?var85', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (87, '?var86', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (88, '?var87', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (89, '?var88', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (90, '?var89', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (91, '?var90', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (92, '?var91', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (93, '?var92', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (94, '?var93', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (95, '?var94', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (96, '?var95', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (97, '?var96', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (98, '?var97', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (99, '?var98', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (100, '?var99', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (101, '?var100', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (102, '?var101', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (103, '?var102', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (104, '?var103', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (105, '?var104', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (106, '?var105', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (107, '?var106', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (108, '?var107', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (109, '?var108', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (110, '?var109', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (111, '?var110', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (112, '?var111', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (113, '?var112', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (114, '?var113', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (115, '?var114', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (116, '?var115', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (117, '?var116', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (118, '?var117', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (119, '?var118', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (120, '?var119', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (121, '?var120', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (122, '?var121', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (123, '?var122', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (124, '?var123', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (125, '?var124', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (126, '?var125', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (127, '?var126', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (128, '?var127', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (129, '?var128', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (130, '?var129', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (131, '?var130', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (132, '?var131', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (133, '?var132', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (134, '?var133', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (135, '?var134', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (136, '?var135', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (137, '?var136', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (138, '?var137', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (139, '?var138', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (140, '?var139', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (141, '?var140', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (142, '?var141', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (143, '?var142', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (144, '?var143', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (145, '?var144', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (146, '?var145', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (147, '?var146', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (148, '?var147', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (149, '?var148', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (150, '?var149', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (151, '?var150', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (152, '?var151', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (153, '?var152', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (154, '?var153', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (155, '?var154', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (156, '?var155', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (157, '?var156', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (158, '?var157', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (159, '?var158', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (160, '?var159', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (161, '?var160', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (162, '?var161', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (163, '?var162', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (164, '?var163', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (165, '?var164', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (166, '?var165', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (167, '?var166', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (168, '?var167', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (169, '?var168', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (170, '?var169', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (171, '?var170', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (172, '?var171', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (173, '?var172', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (174, '?var173', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (175, '?var174', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (176, '?var175', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (177, '?var176', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (178, '?var177', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (179, '?var178', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (180, '?var179', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (181, '?var180', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (182, '?var181', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (183, '?var182', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (184, '?var183', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (185, '?var184', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (186, '?var185', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (187, '?var186', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (188, '?var187', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (189, '?var188', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (190, '?var189', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (191, '?var190', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (192, '?var191', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (193, '?var192', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (194, '?var193', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (195, '?var194', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (196, '?var195', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (197, '?var196', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (198, '?var197', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (199, '?var198', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (200, '?var199', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (201, '?var200', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (202, '?var201', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (203, '?var202', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (204, '?var203', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (205, '?var204', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (206, '?var205', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (207, '?var206', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (208, '?var207', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (209, '?var208', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (210, '?var209', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (211, '?var210', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (212, '?var211', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (213, '?var212', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (214, '?var213', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (215, '?var214', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (216, '?var215', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (217, '?var216', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (218, '?var217', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (219, '?var218', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (220, '?var219', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (221, '?var220', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (222, '?var221', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (223, '?var222', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (224, '?var223', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (225, '?var224', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (226, '?var225', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (227, '?var226', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (228, '?var227', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (229, '?var228', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (230, '?var229', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (231, '?var230', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (232, '?var231', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (233, '?var232', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (234, '?var233', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (235, '?var234', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (236, '?var235', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (237, '?var236', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (238, '?var237', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (239, '?var238', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (240, '?var239', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (241, '?var240', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (242, '?var241', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (243, '?var242', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (244, '?var243', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (245, '?var244', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (246, '?var245', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (247, '?var246', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (248, '?var247', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (249, '?var248', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (250, '?var249', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (251, '?var250', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (252, '?var251', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (253, '?var252', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (254, '?var253', 4, 1);
INSERT INTO VARIABLE_TERM VALUES (255, '?var254', 1, 1);
INSERT INTO VARIABLE_TERM VALUES (256, '?var255', 4, 1);
CALL SYSCS_UTIL.SYSCS_UPDATE_STATISTICS('APP', 'VARIABLE_TERM', null);
SELECT * FROM VARIABLE_TERM WHERE TERM_ID = 11;
SELECT * FROM VARIABLE_TERM WHERE (TERM_ID = 11) OR (TERM_ID =21) OR (TERM_ID =
31);
SELECT * FROM VARIABLE_TERM WHERE (TERM_ID IN (11, 21, 31));
> Can't bulk load rows by primary key efficiently on tables with >256 rows
> ------------------------------------------------------------------------
>
> Key: DERBY-6045
> URL: https://issues.apache.org/jira/browse/DERBY-6045
> Project: Derby
> Issue Type: Bug
> Components: Store
> Affects Versions: 10.9.1.0
> Environment: Linux Debian 6.0.5
> Reporter: Tony Brusseau
> Priority: Critical
>
> 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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