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https://issues.apache.org/jira/browse/DRILL-2157?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14375041#comment-14375041
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Aman Sinha commented on DRILL-2157:
-----------------------------------
Most of the issues listed here have been fixed by DRILL-2353 and are available
in the 0.8 release. This includes filters that have range conditions (between,
<, > etc.) and filters on subdirectories without specifying parent directory.
I am not completely sure about the casting issue since I could not reproduce
the original issue.
I am marking this as fixed for 0.8. [~aengelbrecht] could you please try the
0.8 release and verify ? If there are remaining issues, pls open a new JIRA.
> Directory pruning on subdirectories only and data type conversions for
> directory filters
> ----------------------------------------------------------------------------------------
>
> Key: DRILL-2157
> URL: https://issues.apache.org/jira/browse/DRILL-2157
> Project: Apache Drill
> Issue Type: Improvement
> Components: Query Planning & Optimization
> Affects Versions: Future
> Reporter: Andries Engelbrecht
> Assignee: Aman Sinha
> Priority: Minor
> Fix For: 0.8.0
>
>
> Drill will scan all files and directories when using only a subdirectory as a
> predicate. Additionally if the data type for the directory filter is not a
> string and is converted Drill will also first scan all the subdirectories adn
> files before applying the filter.
> My current observation is that for a directory structure as listed below,
> the pruning only works if the full tree is provided. If only a lower level
> directory is supplied in the filter condition Drill only uses it as a
> filter.
> With directory structure as below
> /2015
> /01
> /10
> /11
> /12
> /13
> /14
> Query:
> select count(id) from `/foo` t where dir0='2015' and dir1='01' and
> dir2='10'
> Produces the correct pruning and query plan
> 01-02 Project(id=[$3]): rowcount = 3670316.0, cumulative cost =
> {1.1010948E7 rows, 1.4681284E7 cpu, 0.0 io, 0.0 network, 0.0 memory}, id =
> 28434
> 01-03 Project(dir0=[$0], dir1=[$3], dir2=[$2], id=[$1]):
> rowcount = 3670316.0, cumulative cost = {7340632.0 rows, 1.468128E7 cpu,
> 0.0 io, 0.0 network, 0.0 memory}, id = 28433
> 01-04 Scan(groupscan=[EasyGroupScan [selectionRoot=/foo,
> numFiles=24, columns=[`dir0`, `dir1`, `dir2`, `id`]
> However:
> select count(id) from `/foo` t where dir2='10'
> Produces full scan of all sub directories and only applies a filter
> condition after the fact. Notice the numFiles between the 2, even though it
> lists columns in the base scan
> 01-04 Filter(condition=[=($0, '10')]): rowcount =
> 9423761.7, cumulative cost = {1.88475234E8 rows, 3.76950476E8 cpu, 0.0 io,
> 0.0 network, 0.0 memory}, id = 27470
> 01-05 Project(dir2=[$1], id=[$0]): rowcount =
> 6.2825078E7, cumulative cost = {1.25650156E8 rows, 1.25650164E8 cpu, 0.0
> io, 0.0 network, 0.0 memory}, id = 27469
> 01-06 Scan(groupscan=[EasyGroupScan
> [selectionRoot=/foo, numFiles=405, columns=[`dir2`, `id`]
> Also using the wrong data type for the filter produces a full scan
> select count(id) from `/foo` where dir_year=2015 and dir_month=01 and
> dir_day=14
> Produces
> 01-04 Filter(condition=[AND(=(CAST($1):ANY NOT NULL, 2015),
> =(CAST($2):ANY NOT NULL, 1), =(CAST($3):ANY NOT NULL, 10))]): rowcount =
> 212034.63825, cumulative cost = {1.88475234E8 rows, 1.005201264E9 cpu, 0.0
> io, 0.0 network, 0.0 memory}, id = 34910
> 01-05 Project(id=[$2], dir0=[$3], dir1=[$1], dir2=[$0]):
> rowcount = 6.2825078E7, cumulative cost = {1.25650156E8 rows, 2.51300328E8
> cpu, 0.0 io, 0.0 network, 0.0 memory}, id = 34909
> 01-06 Scan(groupscan=[EasyGroupScan [selectionRoot=/foo,
> numFiles=405, columns=[`id`, `dir0`, `dir1`, `dir2`],
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