Greetings all.
I think I've stumbled onto a way to speed up queries, but am looking for
a second opinion.
I have a table with several secondary indexes, one of which contains the
'Name' & 'Key' fields. I want to perform a generic match on the 'Name'
field,
to return all rows that have Name = "..Jim..".
If I perform my query on the DB file, it will open & search the entire
table,
ignoring the 2nd index because of the wildcards.
If I perform my query directly against the appropriate XG* file, it will
perform the query on a 'mini-table' of just the Name & Key columns, which
should be much smaller than the entire DB table.
Does this make sense?
For example:
Query
Customer.XG1 | Key | Name |
| Check | CheckPlus ..Jim.. |
endQuery
Note that I tried to open a tcursor against the 'Customer.XG1' file & it
wouldn't let me. The query engine must work differently.
Extra credit: by doing a enumIndexStruct on the table, does the iIndexID
column map directly to the 'XG*' name, as 'X' + string(hex(iIndexID + 1))?
I'm guessing this is the case, because the iIndexID values start with 256
and go up by 1 for each additional index.
Thanks,
Jim Moseley
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