Hi,
I have a virtual table.
create table store (id int, stamp int, value blob);
When i execute the following sql
select stamp, to_text(value) from store where id = 42;
I get as expected sqlite3_index_info to have one usable entry with
aConstraint[i].iColumn = 0
aConstraint[i].op == SQLITE_INDEX_CONSTRAINT_EQ
In xBestIndex I set the aConstraintUsage[i].argvIndex value to 1, to indicate
that '42' should be the first argument in corresponding xFilter call.
And in the corresponding xFilter I get a value of 42 as the first argument and
I can initialize the cursor with just one element with id = 42.
When i execute the following sql
select stamp, to_text(value) from store where id = 42 or id = 24;
I am expecting two usable entries in sqlite3_index_info with
aConstraint[i].iColumn = 0 and aConstraint[i].op == SQLITE_INDEX_CONSTRAINT_EQ
for each check
xBestIndex is called twice,
a) once with only one non-usable entry with aConstraint[i].iColumn = 0 and
aConstraint[i].op == SQLITE_INDEX_CONSTRAINT_EQ and
b) once with only one usable entry with aConstraint[i].iColumn = 0 and
aConstraint[i].op == SQLITE_INDEX_CONSTRAINT_EQ.
And the xFilter called corresponds to the first call to xBestIndex. Thus it
does a table scan to find entries (42, 24)
Am i missing something here ?
-venkat murty
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