DATE values describe a particular year/month/day in the form
yyyy-MM-dd. For example: DATE '2019-02-15'. DATE values do not have a
time of day component. The range of values supported for the DATE type
is 0000-01-01 to 9999-12-31.
This initial DATE type support covers TEXT and HBASE fileformats only.
'DateValue' is used as the internal type to represent DATE values.
The changes are as follows:
- Support for DATE literal syntax.
- Explicit casting between DATE and other types (note that invalid
casts will fail with an error just like invalid DECIMAL_V2 casts,
while failed casts to other types do no lead to warning or error):
- from STRING to DATE. The string value must be formatted as
yyyy-MM-dd HH:mm:ss.SSSSSSSSS. The date component is mandatory,
the time component is optional. If the time component is
present, it will be truncated silently.
- from DATE to STRING. The resulting string value is formatted as
yyyy-MM-dd.
- from TIMESTAMP to DATE. The source timestamp's time of day
component is ignored.
- from DATE to TIMESTAMP. The target timestamp's time of day
component is set to 00:00:00.
- Implicit casting between DATE and other types:
- from STRING to DATE if the source string value is used in a
context where a DATE value is expected.
- from DATE to TIMESTAMP if the source date value is used in a
context where a TIMESTAMP value is expected.
- Since STRING -> DATE, STRING -> TIMESTAMP and DATE -> TIMESTAMP
implicit conversions are now all possible, the existing function
overload resolution logic is not adequate anymore.
For example, it resolves the
if(false, '2011-01-01', DATE '1499-02-02') function call to the
if(BOOLEAN, TIMESTAMP, TIMESTAMP) version of the overloaded
function, instead of the if(BOOLEAN, DATE, DATE) version.
This is clearly wrong, so the function overload resolution logic had
to be changed to resolve function calls to the best-fit overloaded
function definition if there are multiple applicable candidates.
An overloaded function definition is an applicable candidate for a
function call if each actual parameter in the function call either
matches the corresponding formal parameter's type (without casting)
or is implicitly castable to that type.
When looking for the best-fit applicable candidate, a parameter
match score (i.e. the number of actual parameters in the function
call that match their corresponding formal parameter's type without
casting) is calculated and the applicable candidate with the highest
parameter match score is chosen.
There's one more issue that the new resolution logic has to address:
if two applicable candidates have the same parameter match score and
the only difference between the two is that the first one requires a
STRING -> TIMESTAMP implicit cast for some of its parameters while
the second one requires a STRING -> DATE implicit cast for the same
parameters then the first candidate has to be chosen not to break
backward compatibility.
E.g: year('2019-02-15') function call must resolve to
year(TIMESTAMP) instead of year(DATE). Note, that year(DATE) is not
implemented yet, so this is not an issue at the moment but it will
be in the future.
When the resolution algorithm considers overloaded function
definitions, first it orders them lexicographically by the types in
their parameter lists. To ensure the backward compatible behavior
Primitivetype.DATE enum value has to come after
PrimitiveType.TIMESTAMP.
- Codegen infrastructure changes for expression evaluation.
- 'IS [NOT] NULL' and '[NOT] IN' predicates.
- Common comparison operators (including the 'BETWEEN' operator).
- Infrastructure changes for built-in functions.
- Some built-in functions: conditional, aggregate, analytical and
math functions.
- C++ UDF/UDA support.
- Support partitioning and grouping by DATE.
- Beeswax, HiveServer2 support.
These items are tightly coupled and it makes sense to implement them
in one change-set.
Testing:
- A new partitioned TEXT table 'functional.date_tbl' (and the
corresponding HBASE table 'functional_hbase.date_tbl') was
introduced for DATE-related tests.
- BE and FE tests were extended to cover DATE type.
- E2E tests:
- since DATE type is supported for TEXT and HBASE fileformats
only, most DATE tests were implemented separately in
tests/query_test/test_date_queries.py.
Note, that this change-set is not a complete DATE type implementation,
but it lays the foundation for future work:
- Add date support to the random query generator.
- Implement a complete set of built-in functions.
- Add Parquet support.
- Add Kudu support.
- Optionally support Avro and ORC.
For further details, see IMPALA-6169.
Change-Id: Iea8155ef09557e0afa2f8b2d0b2dc9d0896dc30f
Reviewed-on: http://gerrit.cloudera.org:8080/12481
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
As part of the ASF transition, we need to replace references to
Cloudera in Impala with references to Apache. This primarily means
changing Java package names from com.cloudera.impala.* to
org.apache.impala.*
A prior patch renamed all the files as necessary, and this patch
performs the actual code changes. Most of the changes in this patch
were generated with some commands of the form:
find . | grep "\.java\|\.py\|\.h\|\.cc" | \
xargs sed -i s/'com\(.\)cloudera\(\.\)impala/org\1apache\2impala/g
along with some manual fixes.
After this patch, the remaining references to Cloudera in the repo
mostly fall into the categories:
- External components that have cloudera in their own package names,
eg. com.cloudera.kudu/llama
- URLs, eg. https://repository.cloudera.com/
Change-Id: I0d35fa6602a7fc0c212b2ef5e2b3322b77dde7e2
Reviewed-on: http://gerrit.cloudera.org:8080/3937
Reviewed-by: Thomas Tauber-Marshall <tmarshall@cloudera.com>
Reviewed-by: Jim Apple <jbapple@cloudera.com>
Tested-by: Internal Jenkins
For files that have a Cloudera copyright (and no other copyright
notice), make changes to follow the ASF source file header policy here:
http://www.apache.org/legal/src-headers.html#headers
Specifically:
1) Remove the Cloudera copyright.
2) Modify NOTICE.txt according to
http://www.apache.org/legal/src-headers.html#notice
to follow that format and add a line for Cloudera.
3) Replace or add the existing ASF license text with the one given
on the website.
Much of this change was automatically generated via:
git grep -li 'Copyright.*Cloudera' > modified_files.txt
cat modified_files.txt | xargs perl -n -i -e 'print unless m#Copyright.*Cloudera#i;'
cat modified_files_txt | xargs fix_apache_license.py [1]
Some manual fixups were performed following those steps, especially when
license text was completely missing from the file.
[1] https://gist.github.com/anonymous/ff71292094362fc5c594 with minor
modification to ORIG_LICENSE to match Impala's license text.
Change-Id: I2e0bd8420945b953e1b806041bea4d72a3943d86
Reviewed-on: http://gerrit.cloudera.org:8080/3779
Reviewed-by: Dan Hecht <dhecht@cloudera.com>
Tested-by: Internal Jenkins
The SOURCE keyword was introduced for DATA SOURCE ddl commands, but
it is also a very common identifier. This removes the SOURCE and
SOURCES keywords and instead uses DATASOURCE and DATASOURCES.
Change-Id: Ic6c2897d1e23efa169aa8787752fe4aa2bb125d5
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2895
Reviewed-by: Matthew Jacobs <mj@cloudera.com>
Tested-by: jenkins
(cherry picked from commit 267c13f9b46d249bfd1b8711fd3fadf6853dc1ef)
