aggressive for the cases where there is a join and outer loops contain
IN operators. Fix this. Test case in TH3.
FossilOrigin-Name: ccd3bae14b6b47bb0f9622700c04db989f76ce65e10e0709964cfd0675eca762
[/info/b8ba2f17f938c035|check-in b8ba2f17f938c035] to fix the performance
regression identified by
[forum:/forumpost/623f571482|forum post 623f571482].
FossilOrigin-Name: 188772a1dbaf066fbddd39c718fdd87478b19a920622f4640bcb79d4ef065331
sqlite3ExprSkipCollateAndLikely() is never NULL in some of its use cases.
FossilOrigin-Name: 76d2eb86e109fc3cbdba2e8175c22ed7660b59bb9315f6c55c565587f33ad43b
an index when most of the rows will be selected. This branch is trying to
tune the query planner to make that happen more often.
FossilOrigin-Name: 0f42099ad65855c94af8472f3a6fddac7fc2a82e8fdfcc06a298eb6683a28688
Problem reported [forum:/info/80a9c47769772207|by forum post 80a9c47769772207].
FossilOrigin-Name: 883da4dadc88809192e4ed2f753f8883471fb43aa330bc58b017c66e1acedc6c
IN-earlyout optimization because the OP_IfNoHope opcode might move the
cursor.
FossilOrigin-Name: f3c36b840c9a29c0add28039db216f4207a308e5057fc76e3f0004024a8267ac
where the statistics deceive the query planner into using a scan when
an indexed lookup would be better. This check-in changes the code
generation to do the IN-scan using a new OP_SeekScan opcode. That new
opcode is designed to abandon the scan and fall back to a seek if
it doesn't find a match quickly enough. For this work-in-progress check-in,
OP_SeekScan is still a no-op and OP_SeekGE still ends up doing all the work.
FossilOrigin-Name: d720b6981eeb0ffdb14494ca63eca298ee724ae4ad4863c7c7cbfdad7fa52519
DISTINCT by B-Tree by half, under the assumption that the DISTINCT will
eliminate about half the rows of output. This is really a wild guess. But
we do not have any better way of estimating what the row-count reduction due
to DISTINCT will actually be.
FossilOrigin-Name: 8787417ec1da8071d84c6ff0d7a90b5fd458ab6baba871327f36bc4e1bceca61
index accesses. Code is now slightly smaller and faster than trunk.
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using the index rather than the main table, so as to avoid unnecessary
main table seeks.
FossilOrigin-Name: 2f7cb6ab39e54fd6eb3a280d3022c3d4f4ed92e83af7226e63e0199a96397a6b
crossing over LEFT JOINs, as long as the table being moved is not the
right table of the LEFT JOIN.
FossilOrigin-Name: c1ea064948ba08c4be209ad6efc2126a7367bcb06266ea35eb957bf2d4e2cb9f
operator in the ON clause, put the OP_IfNoHope operator after the
OP_IfNotOpen operator, not before, to avoid a (harmless) uninitialized
register reference. Ticket [82b588d342d515d1]
FossilOrigin-Name: 8b437b47266ec2d80d85eafcfdd6949556d6c28d9d67d5f43d89799f0f5b7bd0
a term is seen to be of low selectivity, it merely sets a new flag
(the TERM_HIGHTRUTH flag) which causes whereLoopOutputAdjust() to ignore
that term.
FossilOrigin-Name: 4558163b6a525990f0f1b6629dbb76daf49bcaf1ddbaf0c50fe05ce9ee480ff8
is less than the heuristic value, as there could be correlations unknown to
stat4. Also add additional tracing output to make truthProb adjustments more
visible.
FossilOrigin-Name: c535fea147ce5c6e4aab25d3c85a3f53a7364c5b5ee10fb6d393c5911a02be7e
probability of WHERE clause terms that do not participate in the index.
FossilOrigin-Name: 1babd6ec5d60e2c34aa1c0285ead768a88004218468e97262411973fe3487022
index are already used for non-equality constraints.
Ticket [304017f5f04a0035]
FossilOrigin-Name: d7126a9ced86cb0934d5bde2bf535e6b529c361444c99e723f29dd3eb36e7044
has not already completed. Also add the sqlite3WhereUsesDeferredSeek()
interface to the query planner. The UPDATE implementation adds an
OP_FinishSeek before running the final OP_Insert if one is needed.
Ticket [ec8abb025e78f40c] and also an assertion fault reported by Yongheng.
FossilOrigin-Name: 21ef6e99331210b80fa7c71b4f02e8f768a748d01aef884368af2f6b51a067e0
before and after coding each loop. The 0x800 flag shows status at the start
and at the end of each loop. An extra "C" tag is shown on coded terms.
FossilOrigin-Name: 59cc46e5a6d8dbb030f27716ad5446ecccf81cf0cfff95338b9133777f2059e7
that is used to communicate with virtual table modules. Avoid adding
unused constraints to the sqlite3_index_info structure. Extra constraints
are harmless, but might be confusing to people trying to understand the code.
FossilOrigin-Name: 5e6357fc953a955d8ebb5c1fcd72e04e4ae5e8bf5941810015c2fbc50de70535
at the top of each iteration of the loop in order to prevent spurious
OP_SCopy misuse complaints. Ticket [de4b04149b9fdeae]
FossilOrigin-Name: 6afadd3b3a40b0ef29fd14fb24c2a4b9479483e5f8b9125ce02d8daae662207f
drh