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36 check-ins using file test/whereL.test version 786ae3e0

Add the PRAGMA table_vinfo command (with an extra "v" before "info") that works like PRAGMA table_info (without the "v") except that it also shows hidden columns on virtual tables. (check-in: 8bcd1a59 user: drh tags: pragma-table-vinfo)
Minor style improvements. (check-in: 60bbca2b user: mistachkin tags: trunk)
Allow sqlite3_snapshot_open() to be called to change the snapshot after a read transaction is already open on database. (Closed-Leaf check-in: 051ac015 user: dan tags: exp-snapshot-open)
Enhance the edit() function so that it converts text from \r\n back into \n only if the original unedited copy contained no \r\n values. (check-in: 20c995d3 user: drh tags: trunk)
Add the --info option to the fuzzcheck test utility. (check-in: 1caaaaa7 user: drh tags: trunk)
Fix an overzealous assert() statement discovered by OSSFuzz. (check-in: d9c9fe9f user: drh tags: trunk)
Remove the column-cache from the code generator. The column-cache has been a persistent source of bugs for years and with recent improvements in the performance of OP_Column, it no longer provides a benefit. After the column cache is removed, the binary is almost 2KB smaller and the speed-check.sh performance test is over 3 million cycles faster. (check-in: cdff3af7 user: drh tags: trunk)
Remove a testcase() that is no longer reachable without the column cache. Provide an assert() to help prove that the testcase is no longer reachable. (Closed-Leaf check-in: a500893b user: drh tags: omit-column-cache)
Fix comments that were made obsolete by the removal of the column cache. (check-in: 2041231d user: drh tags: omit-column-cache)
Remove more column-cache residue: The OP_SetColTab and OP_VerifyColTab opcodes and the associated SQLITE_DEBUG_COLUMNCACHE logic. (check-in: 80236e81 user: drh tags: omit-column-cache)
Further logic simplifications that flow out of the omission of the column cache. (check-in: 7d9072b0 user: drh tags: omit-column-cache)
Add test cases for the constant expression fix of the previous check-in. (check-in: 95db5bd9 user: drh tags: trunk)
Ensure that all expressions that are to be evaluated once at the start of a prepared statement (the Parse.pConstExpr expressions) pass the sqlite3ExprIsConstantNotJoin() test. It is not sufficient to pass just the sqlite3ExprIsConstant() test as that would allow through column references that are bound to constants by the WHERE clause in the constant propagation optimization. This fixes a problem discovered by OSSFuzz. (check-in: 8bc7f84c user: drh tags: trunk)
Remove additional traces of the column cache. (check-in: db6052e9 user: drh tags: omit-column-cache)
Completely remove the column cache logic, which has been a persistent source of bugs for many years. Due to recent enhancements to the performance of the OP_Column opcode, removing the column cache actually makes speed-check.sh run faster. Removing the column cache also saves about 1,800 bytes of code space. (check-in: 3f5f60cd user: drh tags: omit-column-cache)
Fix the handling of sub-queries with LIMIT clauses by the optimization activated by compile-time symbol SQLITE_COUNTOFVIEW_OPTIMIZATION. (check-in: 21235d9a user: dan tags: trunk)
Fix the OP_SeekRowid opcode so that it has no type-change side-effects on the key register in P3. This fixes an obcure problem that arises when doing equi-joins between a table with a TEXT column against another table with an INTEGER PRIMARY KEY. The original problem was discovered when OSSFuzz created such a query and hit an assert() in OP_VerifyTabCol that was specifically designed to catch these kinds of errors at run-time. Test cases for this fix are in TH3. (check-in: fa94b49e user: drh tags: trunk)
Improve "PRAGMA vdbe_trace=ON" to always show the key values for the OP_IdxGT and related opcodes. (check-in: 0f881955 user: drh tags: trunk)
In the command-line shell, always exit if realloc() fails. (check-in: e390023c user: drh tags: trunk)
Add a small cost penalty to sorting to bias the query planner in favor of plans that do not require a final sorting pass. (check-in: 85b9beb4 user: drh tags: trunk)
Do not allow a column reference that is converted into a constant by the WHERE-clause constant propagation optimization to be moved to the init-time constant expression list, as the table reference will not work there. This fixes a problem found by OSSFuzz. (check-in: d30b2a94 user: drh tags: trunk)
Fix an assert() statement that was made obsolete by the constant propagation enhancement. Problem discovered by OSSFuzz. (check-in: e4b4737e user: drh tags: trunk)
Improved debugging output when the ".selecttrace" option is used in the shell. (check-in: fcb88dd6 user: drh tags: trunk)
An early attempt at refactoring Expr (Closed-Leaf check-in: fc90a53d user: drh tags: expr-simplify-branch1)
Add assert() statements to sqlite3ExprDelete() that prove various symmetry properties of the Expr object that might be exploited to make the Expr object smaller and faster. (check-in: 81f25d5c user: drh tags: expr-simplify)
Improvements to the parser to increase coverage. Fix the parser so that at least one expresssion is required after PARTITION BY and within the list of expressions on VALUES(). (check-in: 02204f8b user: drh tags: trunk)
When doing a DROP VIEW do not try to delete entries from the sqlite_stat1 table as there are none. (check-in: 7efdba2b user: drh tags: trunk)
Minor grammar changes that help the parser run faster by reducing the number of NUL rule reductions. (check-in: cfd1b005 user: drh tags: trunk)
Enhance Makefile for MSVC to support building the shell tool without using the amalgamation. (check-in: 3d815d83 user: mistachkin tags: trunk)
The WHERE-clause constant propagation optimization attempts to use transitive laws to replace column values with constants in the WHERE clause in order to help to query planner make more aggressive optimizations. (check-in: f4229707 user: drh tags: trunk)
Reduce the performance cost of the constant propagation optimization to less than 200,000 cycles. (Closed-Leaf check-in: 865249de user: drh tags: propagate-const-opt)
Performance improvement to sqlite3ExprCollSeq(). With this change, the performance of speed-check.sh is within 400,000 cycles of trunk. (check-in: a5f86f49 user: drh tags: propagate-const-opt)
Faster implementation of sqlite3IsBinary(). (check-in: be05d0db user: drh tags: propagate-const-opt)
Only run the constant propagation optimization on joins since that is the only scenario where it is useful. This saves prepare time for the common case of a simple query. (check-in: 598d6083 user: drh tags: propagate-const-opt)
Constant propagation is now restricted to just the WHERE clause. The mechanism is changed to take affinity and collation into account. This seems to give correct answers. But the search for constant propagation costs 4 million cycles in the speed test. (check-in: 82c67efb user: drh tags: propagate-const-opt)
Add a test case demonstrating the collation problem with constant propagation. (check-in: 50add839 user: drh tags: propagate-const-opt)