If pandas is broken (can't be imported, raise other exceptions other than ImportError), pyspark can't be imported, we should ignore all the exceptions.

Author: Davies Liu <davies@databricks.com>

Closes #8173 from davies/fix_pandas.

Also we could create a Python UDT without having a Scala one, it's important for Python users.

cc mengxr JoshRosen

Author: Davies Liu <davies@databricks.com>

Closes #7453 from davies/class_in_main and squashes the following commits:

4dfd5e1 [Davies Liu] add tests for Python and Scala UDT
793d9b2 [Davies Liu] Merge branch 'master' of github.com:apache/spark into class_in_main
dc65f19 [Davies Liu] address comment
a9a3c40 [Davies Liu] Merge branch 'master' of github.com:apache/spark into class_in_main
a86e1fc [Davies Liu] fix serialization
ad528ba [Davies Liu] Merge branch 'master' of github.com:apache/spark into class_in_main
63f52ef [Davies Liu] fix pylint check
655b8a9 [Davies Liu] Merge branch 'master' of github.com:apache/spark into class_in_main
316a394 [Davies Liu] support Python UDT with UTF
0bcb3ef [Davies Liu] fix bug in mllib
de986d6 [Davies Liu] fix test
83d65ac [Davies Liu] fix bug in StructType
55bb86e [Davies Liu] support Python UDT in __main__ (without Scala one)

This PR also remove the duplicated code between registerFunction and UserDefinedFunction.

cc JoshRosen

Author: Davies Liu <davies@databricks.com>

Closes #7450 from davies/fix_return_type and squashes the following commits:

e80bf9f [Davies Liu] remove debugging code
f94b1f6 [Davies Liu] fix mima
8f9c58b [Davies Liu] convert returned object from UDF into internal type

[SPARK-7902] [SPARK-6289] [SPARK-8685] [SQL] [PYSPARK] Refactor of serialization for Python DataFrame

This PR fix the long standing issue of serialization between Python RDD and DataFrame, it change to using a customized Pickler for InternalRow to enable customized unpickling (type conversion, especially for UDT), now we can support UDT for UDF, cc mengxr .

There is no generated `Row` anymore.

Author: Davies Liu <davies@databricks.com>

Closes #7301 from davies/sql_ser and squashes the following commits:

81bef71 [Davies Liu] address comments
e9217bd [Davies Liu] add regression tests
db34167 [Davies Liu] Refactor of serialization for Python DataFrame

[SPARK-8535] [PYSPARK] PySpark : Can't create DataFrame from Pandas dataframe with no explicit column name

Because implicit name of `pandas.columns` are Int, but `StructField` json expect `String`.
So I think `pandas.columns` are should be convert to `String`.

### issue

* [SPARK-8535 PySpark : Can't create DataFrame from Pandas dataframe with no explicit column name](https://issues.apache.org/jira/browse/SPARK-8535)

Author: x1- <viva008@gmail.com>

Closes #7124 from x1-/SPARK-8535 and squashes the following commits:

d68fd38 [x1-] modify unit-test using pandas.
ea1897d [x1-] For implicit name of pandas.columns are Int, so should be convert to String.

Capture the AnalysisException in SQL, hide the long java stack trace, only show the error message.

cc rxin

Author: Davies Liu <davies@databricks.com>

Closes #7135 from davies/ananylis and squashes the following commits:

dad7ae7 [Davies Liu] add comment
ec0c0e8 [Davies Liu] Update utils.py
cdd7edd [Davies Liu] add doc
7b044c2 [Davies Liu] fix python 3
f84d3bd [Davies Liu] capture SQL AnalysisException in Python API

Avoid the unnecessary jobs when infer schema from list.

cc yhuai mengxr

Author: Davies Liu <davies@databricks.com>

Closes #6606 from davies/improve_create and squashes the following commits:

a5928bf [Davies Liu] Update MimaExcludes.scala
62da911 [Davies Liu] fix mima
bab4d7d [Davies Liu] Merge branch 'improve_create' of github.com:davies/spark into improve_create
eee44a8 [Davies Liu] Merge branch 'master' of github.com:apache/spark into improve_create
8d9292d [Davies Liu] Update context.py
eb24531 [Davies Liu] Update context.py
c969997 [Davies Liu] bug fix
d5a8ab0 [Davies Liu] fix tests
8c3f10d [Davies Liu] Merge branch 'master' of github.com:apache/spark into improve_create
6ea5925 [Davies Liu] address comments
6ceaeff [Davies Liu] avoid spark jobs in createDataFrame

Currently we auto alias expression in parser. However, during parser phase we don't have enough information to do the right alias. For example, Generator that has more than 1 kind of element need MultiAlias, ExtractValue don't need Alias if it's in middle of a ExtractValue chain.

Author: Wenchen Fan <cloud0fan@outlook.com>

Closes #6647 from cloud-fan/alias and squashes the following commits:

552eba4 [Wenchen Fan] fix python
5b5786d [Wenchen Fan] fix agg
73a90cb [Wenchen Fan] fix case-preserve of ExtractValue
4cfd23c [Wenchen Fan] fix order by
d18f401 [Wenchen Fan] refine
9f07359 [Wenchen Fan] address comments
39c1aef [Wenchen Fan] small fix
33640ec [Wenchen Fan] auto alias expressions in analyzer

1. range() overloaded in SQLContext.scala
2. range() modified in python sql context.py
3. Tests added accordingly in DataFrameSuite.scala and python sql tests.py

Author: animesh <animesh@apache.spark>

Closes #6609 from animeshbaranawal/SPARK-7980 and squashes the following commits:

935899c [animesh] SPARK-7980:python+scala changes

Author: Reynold Xin <rxin@databricks.com>

Closes #6601 from rxin/python-read-write-test-and-doc and squashes the following commits:

baa8ad5 [Reynold Xin] Code review feedback.
f081d47 [Reynold Xin] More documentation updates.
c9902fa [Reynold Xin] [SPARK-8060] Improve DataFrame Python reader/writer interface doc and testing.

1. ntile should take an integer as parameter.
2. Added Python API (based on #6364)
3. Update documentation of various DataFrame Python functions.

Author: Davies Liu <davies@databricks.com>
Author: Reynold Xin <rxin@databricks.com>

Closes #6374 from rxin/window-final and squashes the following commits:

69004c7 [Reynold Xin] Style fix.
288cea9 [Reynold Xin] Update documentaiton.
7cb8985 [Reynold Xin] Merge pull request #6364 from davies/window
66092b4 [Davies Liu] update docs
ed73cb4 [Reynold Xin] [SPARK-7322][SQL] Improve DataFrame window function documentation.
ef55132 [Davies Liu] Merge branch 'master' of github.com:apache/spark into window4
8936ade [Davies Liu] fix maxint in python 3
2649358 [Davies Liu] update docs
778e2c0 [Davies Liu] SPARK-7836 and SPARK-7822: Python API of window functions

Add version info for public Python SQL API.

cc rxin

Author: Davies Liu <davies@databricks.com>

Closes #6295 from davies/versions and squashes the following commits:

cfd91e6 [Davies Liu] add more version for DataFrame API
600834d [Davies Liu] add version to SQL API docs

cc rxin, please take a quick look, I'm working on tests.

Author: Davies Liu <davies@databricks.com>

Closes #6238 from davies/readwrite and squashes the following commits:

c7200eb [Davies Liu] update tests
9cbf01b [Davies Liu] Merge branch 'master' of github.com:apache/spark into readwrite
f0c5a04 [Davies Liu] use sqlContext.read.load
5f68bc8 [Davies Liu] update tests
6437e9a [Davies Liu] Merge branch 'master' of github.com:apache/spark into readwrite
bcc6668 [Davies Liu] add reader amd writer API in Python

This PR is based on #6081, thanks adrian-wang.

Closes #6081

Author: Daoyuan Wang <daoyuan.wang@intel.com>
Author: Davies Liu <davies@databricks.com>

Closes #6230 from davies/range and squashes the following commits:

d3ce5fe [Davies Liu] add tests
789eda5 [Davies Liu] add range() in Python
4590208 [Davies Liu] Merge commit 'refs/pull/6081/head' of github.com:apache/spark into range
cbf5200 [Daoyuan Wang] let's add python support in a separate PR
f45e3b2 [Daoyuan Wang] remove redundant toLong
617da76 [Daoyuan Wang] fix safe marge for corner cases
867c417 [Daoyuan Wang] fix
13dbe84 [Daoyuan Wang] update
bd998ba [Daoyuan Wang] update comments
d3a0c1b [Daoyuan Wang] add range api()

This PR revert #5404, change to pass the version of python in driver into JVM, check it in worker before deserializing closure, then it can works with different major version of Python.

Author: Davies Liu <davies@databricks.com>

Closes #6203 from davies/py_version and squashes the following commits:

b8fb76e [Davies Liu] fix test
6ce5096 [Davies Liu] use string for version
47c6278 [Davies Liu] check python version of worker with driver

This PR enable auto_convert in JavaGateway, then we could register a converter for a given types, for example, date and datetime.

There are two bugs related to auto_convert, see [1] and [2], we workaround it in this PR.

[1]  https://github.com/bartdag/py4j/issues/160
[2] https://github.com/bartdag/py4j/issues/161

cc rxin JoshRosen

Author: Davies Liu <davies@databricks.com>

Closes #5570 from davies/py4j_date and squashes the following commits:

eb4fa53 [Davies Liu] fix tests in python 3
d17d634 [Davies Liu] rollback changes in mllib
2e7566d [Davies Liu] convert tuple into ArrayList
ceb3779 [Davies Liu] Update rdd.py
3c373f3 [Davies Liu] support date and datetime by auto_convert
cb094ff [Davies Liu] enable auto convert

Author: Elisey Zanko <elisey.zanko@gmail.com>

Closes #5361 from 31z4/spark-6661 and squashes the following commits:

73c5d79 [Elisey Zanko] Python type errors should print type, not object

This PR update PySpark to support Python 3 (tested with 3.4).

Known issue: unpickle array from Pyrolite is broken in Python 3, those tests are skipped.

TODO: ec2/spark-ec2.py is not fully tested with python3.

Author: Davies Liu <davies@databricks.com>
Author: twneale <twneale@gmail.com>
Author: Josh Rosen <joshrosen@databricks.com>

Closes #5173 from davies/python3 and squashes the following commits:

d7d6323 [Davies Liu] fix tests
6c52a98 [Davies Liu] fix mllib test
99e334f [Davies Liu] update timeout
b716610 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
cafd5ec [Davies Liu] adddress comments from @mengxr
bf225d7 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
179fc8d [Davies Liu] tuning flaky tests
8c8b957 [Davies Liu] fix ResourceWarning in Python 3
5c57c95 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
4006829 [Davies Liu] fix test
2fc0066 [Davies Liu] add python3 path
71535e9 [Davies Liu] fix xrange and divide
5a55ab4 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
125f12c [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
ed498c8 [Davies Liu] fix compatibility with python 3
820e649 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
e8ce8c9 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
ad7c374 [Davies Liu] fix mllib test and warning
ef1fc2f [Davies Liu] fix tests
4eee14a [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
20112ff [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
59bb492 [Davies Liu] fix tests
1da268c [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
ca0fdd3 [Davies Liu] fix code style
9563a15 [Davies Liu] add imap back for python 2
0b1ec04 [Davies Liu] make python examples work with Python 3
d2fd566 [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
a716d34 [Davies Liu] test with python 3.4
f1700e8 [Davies Liu] fix test in python3
671b1db [Davies Liu] fix test in python3
692ff47 [Davies Liu] fix flaky test
7b9699f [Davies Liu] invalidate import cache for Python 3.3+
9c58497 [Davies Liu] fix kill worker
309bfbf [Davies Liu] keep compatibility
5707476 [Davies Liu] cleanup, fix hash of string in 3.3+
8662d5b [Davies Liu] Merge branch 'master' of github.com:apache/spark into python3
f53e1f0 [Davies Liu] fix tests
70b6b73 [Davies Liu] compile ec2/spark_ec2.py in python 3
a39167e [Davies Liu] support customize class in __main__
814c77b [Davies Liu] run unittests with python 3
7f4476e [Davies Liu] mllib tests passed
d737924 [Davies Liu] pass ml tests
375ea17 [Davies Liu] SQL tests pass
6cc42a9 [Davies Liu] rename
431a8de [Davies Liu] streaming tests pass
78901a7 [Davies Liu] fix hash of serializer in Python 3
24b2f2e [Davies Liu] pass all RDD tests
35f48fe [Davies Liu] run future again
1eebac2 [Davies Liu] fix conflict in ec2/spark_ec2.py
6e3c21d [Davies Liu] make cloudpickle work with Python3
2fb2db3 [Josh Rosen] Guard more changes behind sys.version; still doesn't run
1aa5e8f [twneale] Turned out `pickle.DictionaryType is dict` == True, so swapped it out
7354371 [twneale] buffer --> memoryview  I'm not super sure if this a valid change, but the 2.7 docs recommend using memoryview over buffer where possible, so hoping it'll work.
b69ccdf [twneale] Uses the pure python pickle._Pickler instead of c-extension _pickle.Pickler. It appears pyspark 2.7 uses the pure python pickler as well, so this shouldn't degrade pickling performance (?).
f40d925 [twneale] xrange --> range
e104215 [twneale] Replaces 2.7 types.InstsanceType with 3.4 `object`....could be horribly wrong depending on how types.InstanceType is used elsewhere in the package--see http://bugs.python.org/issue8206
79de9d0 [twneale] Replaces python2.7 `file` with 3.4 _io.TextIOWrapper
2adb42d [Josh Rosen] Fix up some import differences between Python 2 and 3
854be27 [Josh Rosen] Run `futurize` on Python code:
7c5b4ce [Josh Rosen] Remove Python 3 check in shell.py.

<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/apache/spark/5349)
<!-- Reviewable:end -->

Author: Cheng Lian <lian@databricks.com>

Closes #5349 from liancheng/py-refresh-table and squashes the following commits:

004bec0 [Cheng Lian] Adds HiveContext.refreshTable to PySpark

Use `sqlContext` in PySpark shell, make it consistent with SQL programming guide. `sqlCtx` is also kept for compatibility.

Author: Davies Liu <davies@databricks.com>

Closes #5425 from davies/sqlCtx and squashes the following commits:

af67340 [Davies Liu] sqlCtx -> sqlContext
15a278f [Davies Liu] use sqlContext in python shell

Author: Reynold Xin <rxin@databricks.com>

Closes #5287 from rxin/pyspark-df-doc-cleanup-context and squashes the following commits:

1841b60 [Reynold Xin] Lint.
f2007f1 [Reynold Xin] functions and types.
bc3b72b [Reynold Xin] More improvements to DataFrame Python doc.
ac1d4c0 [Reynold Xin] Bug fix.
b163365 [Reynold Xin] Python fix. Added Experimental flag to DataFrameNaFunctions.
608422d [Reynold Xin] [Doc] Cleanup context.py Python docs.

This PR create an alias for `registerFunction` as `udf.register`, to be consistent with Scala API.

It also deprecated inferSchema() and applySchema(), show an warning for them.

cc rxin

Author: Davies Liu <davies@databricks.com>

Closes #5273 from davies/udf and squashes the following commits:

476e947 [Davies Liu] address comments
c096fdb [Davies Liu] add SQLContext.udf and deprecate inferSchema() and applySchema

The _eq_ of DataType is not correct, class cache is not use correctly (created class can not be find by dataType), then it will create lots of classes (saved in _cached_cls), never released.

Also, all same DataType have same hash code, there will be many object in a dict with the same hash code, end with hash attach, it's very slow to access this dict (depends on the implementation of CPython).

This PR also improve the performance of inferSchema (avoid the unnecessary converter of object).

cc pwendell  JoshRosen

Author: Davies Liu <davies@databricks.com>

Closes #4808 from davies/leak and squashes the following commits:

6a322a4 [Davies Liu] tests refactor
3da44fc [Davies Liu] fix __eq__ of Singleton
534ac90 [Davies Liu] add more checks
46999dc [Davies Liu] fix tests
d9ae973 [Davies Liu] fix memory leak in sql

select empty should NOT be the same as select. make sure selectExpr is behaving the same.
join param documentation
link to source doesn't work in jekyll generated file
cross reference of columns (i.e. enabling linking)
show(): move df example before df.show()
move tests in SQLContext out of docstring otherwise doc is too long
Column.desc and .asc doesn't have any documentation
in documentation, sort functions.*)

Author: Davies Liu <davies@databricks.com>

Closes #4756 from davies/df_docs and squashes the following commits:

f30502c [Davies Liu] fix doc
32f0d46 [Davies Liu] fix DataFrame docs

Author: Michael Armbrust <michael@databricks.com>

Closes #4684 from marmbrus/explainAnalysis and squashes the following commits:

afbaa19 [Michael Armbrust] fix python
d93278c [Michael Armbrust] fix hive
e5fa0a4 [Michael Armbrust] Merge remote-tracking branch 'origin/master' into explainAnalysis
52119f2 [Michael Armbrust] more tests
82a5431 [Michael Armbrust] fix tests
25753d2 [Michael Armbrust] Merge remote-tracking branch 'origin/master' into explainAnalysis
aee1e6a [Michael Armbrust] fix hive
b23a844 [Michael Armbrust] newline
de8dc51 [Michael Armbrust] more comments
acf620a [Michael Armbrust] [SPARK-5873][SQL] Show partially analyzed plans in query execution

Fix createDataFrame() from pandas DataFrame (not tested by jenkins, depends on SPARK-5693).

It also support to create DataFrame from plain tuple/list without column names, `_1`, `_2` will be used as column names.

Author: Davies Liu <davies@databricks.com>

Closes #4679 from davies/pandas and squashes the following commits:

c0cbe0b [Davies Liu] fix tests
8466d1d [Davies Liu] fix create DataFrame from pandas

JIRA: https://issues.apache.org/jira/browse/SPARK-5909

Author: Yin Huai <yhuai@databricks.com>

Closes #4694 from yhuai/clearCache and squashes the following commits:

397ecc4 [Yin Huai] Address comments.
a2702fc [Yin Huai] Update parser.
3a54506 [Yin Huai] add isEmpty to CacheManager.
6d14460 [Yin Huai] Python clearCache.
f7b8dbd [Yin Huai] Add clear cache command.

Author: Michael Armbrust <michael@databricks.com>

Closes #4642 from marmbrus/docs and squashes the following commits:

d291c34 [Michael Armbrust] python tests
9be66e3 [Michael Armbrust] comments
d56afc2 [Michael Armbrust] fix style
f004747 [Michael Armbrust] fix build
c4a907b [Michael Armbrust] fix tests
42e2b73 [Michael Armbrust] [SQL] Documentation / API Clean-up.

Added a bunch of tags.

Also changed parquetFile to take varargs rather than a string followed by varargs.

Author: Reynold Xin <rxin@databricks.com>

Closes #4636 from rxin/df-doc and squashes the following commits:

651f80c [Reynold Xin] Fixed parquetFile in PySpark.
8dc3024 [Reynold Xin] [SQL] Various DataFrame doc changes.

- The old implicit would convert RDDs directly to DataFrames, and that added too many methods.
- toDataFrame -> toDF
- Dsl -> functions
- implicits moved into SQLContext.implicits
- addColumn -> withColumn
- renameColumn -> withColumnRenamed

Python changes:
- toDataFrame -> toDF
- Dsl -> functions package
- addColumn -> withColumn
- renameColumn -> withColumnRenamed
- add toDF functions to RDD on SQLContext init
- add flatMap to DataFrame

Author: Reynold Xin <rxin@databricks.com>
Author: Davies Liu <davies@databricks.com>

Closes #4556 from rxin/SPARK-5752 and squashes the following commits:

5ef9910 [Reynold Xin] More fix
61d3fca [Reynold Xin] Merge branch 'df5' of github.com:davies/spark into SPARK-5752
ff5832c [Reynold Xin] Fix python
749c675 [Reynold Xin] count(*) fixes.
5806df0 [Reynold Xin] Fix build break again.
d941f3d [Reynold Xin] Fixed explode compilation break.
fe1267a [Davies Liu] flatMap
c4afb8e [Reynold Xin] style
d9de47f [Davies Liu] add comment
b783994 [Davies Liu] add comment for toDF
e2154e5 [Davies Liu] schema() -> schema
3a1004f [Davies Liu] Dsl -> functions, toDF()
fb256af [Reynold Xin] - toDataFrame -> toDF - Dsl -> functions - implicits moved into SQLContext.implicits - addColumn -> withColumn - renameColumn -> withColumnRenamed
0dd74eb [Reynold Xin] [SPARK-5752][SQL] Don't implicitly convert RDDs directly to DataFrames
97dd47c [Davies Liu] fix mistake
6168f74 [Davies Liu] fix test
1fc0199 [Davies Liu] fix test
a075cd5 [Davies Liu] clean up, toPandas
663d314 [Davies Liu] add test for agg('*')
9e214d5 [Reynold Xin] count(*) fixes.
1ed7136 [Reynold Xin] Fix build break again.
921b2e3 [Reynold Xin] Fixed explode compilation break.
14698d4 [Davies Liu] flatMap
ba3e12d [Reynold Xin] style
d08c92d [Davies Liu] add comment
5c8b524 [Davies Liu] add comment for toDF
a4e5e66 [Davies Liu] schema() -> schema
d377fc9 [Davies Liu] Dsl -> functions, toDF()
6b3086c [Reynold Xin] - toDataFrame -> toDF - Dsl -> functions - implicits moved into SQLContext.implicits - addColumn -> withColumn - renameColumn -> withColumnRenamed
807e8b1 [Reynold Xin] [SPARK-5752][SQL] Don't implicitly convert RDDs directly to DataFrames

https://issues.apache.org/jira/browse/SPARK-3299

Author: Yin Huai <yhuai@databricks.com>

Closes #4547 from yhuai/tables and squashes the following commits:

6c8f92e [Yin Huai] Add tableNames.
acbb281 [Yin Huai] Update Python test.
7793dcb [Yin Huai] Fix scala test.
572870d [Yin Huai] Address comments.
aba2e88 [Yin Huai] Format.
12c86df [Yin Huai] Add tables() to SQLContext to return a DataFrame containing existing tables.

1. DataFrame.renameColumn

2. DataFrame.show() and _repr_

3. Use simpleString() rather than jsonValue in DataFrame.dtypes

4. createDataFrame from local Python data, including pandas.DataFrame

Author: Davies Liu <davies@databricks.com>

Closes #4528 from davies/df3 and squashes the following commits:

014acea [Davies Liu] fix typo
6ba526e [Davies Liu] fix tests
46f5f95 [Davies Liu] address comments
6cbc154 [Davies Liu] dataframe.show() and improve dtypes
6f94f25 [Davies Liu] create DataFrame from local Python data

Deprecate inferSchema() and applySchema(), use createDataFrame() instead, which could take an optional `schema` to create an DataFrame from an RDD. The `schema` could be StructType or list of names of columns.

Author: Davies Liu <davies@databricks.com>

Closes #4498 from davies/create and squashes the following commits:

08469c1 [Davies Liu] remove Scala/Java API for now
c80a7a9 [Davies Liu] fix hive test
d1bd8f2 [Davies Liu] cleanup applySchema
9526e97 [Davies Liu] createDataFrame from RDD with columns

https://issues.apache.org/jira/browse/SPARK-5658

Author: Yin Huai <yhuai@databricks.com>

This patch had conflicts when merged, resolved by
Committer: Michael Armbrust <michael@databricks.com>

Closes #4446 from yhuai/writeSupportFollowup and squashes the following commits:

f3a96f7 [Yin Huai] davies's comments.
225ff71 [Yin Huai] Use Scala TestHiveContext to initialize the Python HiveContext in Python tests.
2306f93 [Yin Huai] Style.
2091fcd [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
537e28f [Yin Huai] Correctly clean up temp data.
ae4649e [Yin Huai] Fix Python test.
609129c [Yin Huai] Doc format.
92b6659 [Yin Huai] Python doc and other minor updates.
cbc717f [Yin Huai] Rename dataSourceName to source.
d1c12d3 [Yin Huai] No need to delete the duplicate rule since it has been removed in master.
22cfa70 [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
d91ecb8 [Yin Huai] Fix test.
4c76d78 [Yin Huai] Simplify APIs.
3abc215 [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
0832ce4 [Yin Huai] Fix test.
98e7cdb [Yin Huai] Python style.
2bf44ef [Yin Huai] Python APIs.
c204967 [Yin Huai] Format
a10223d [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
9ff97d8 [Yin Huai] Add SaveMode to saveAsTable.
9b6e570 [Yin Huai] Update doc.
c2be775 [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
99950a2 [Yin Huai] Use Java enum for SaveMode.
4679665 [Yin Huai] Remove duplicate rule.
77d89dc [Yin Huai] Update doc.
e04d908 [Yin Huai] Move import and add (Scala-specific) to scala APIs.
cf5703d [Yin Huai] Add checkAnswer to Java tests.
7db95ff [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
6dfd386 [Yin Huai] Add java test.
f2f33ef [Yin Huai] Fix test.
e702386 [Yin Huai] Apache header.
b1e9b1b [Yin Huai] Format.
ed4e1b4 [Yin Huai] Merge remote-tracking branch 'upstream/master' into writeSupportFollowup
af9e9b3 [Yin Huai] DDL and write support API followup.
2a6213a [Yin Huai] Update API names.
e6a0b77 [Yin Huai] Update test.
43bae01 [Yin Huai] Remove createTable from HiveContext.
5ffc372 [Yin Huai] Add more load APIs to SQLContext.
5390743 [Yin Huai] Add more save APIs to DataFrame.

All the DataTypes moved into pyspark.sql.types

The changes can be tracked by `--find-copies-harder -M25`
```
davieslocalhost:~/work/spark/python$ git diff --find-copies-harder -M25 --numstat master..
2       5       python/docs/pyspark.ml.rst
0       3       python/docs/pyspark.mllib.rst
10      2       python/docs/pyspark.sql.rst
1       1       python/pyspark/mllib/linalg.py
21      14      python/pyspark/{mllib => sql}/__init__.py
14      2108    python/pyspark/{sql.py => sql/context.py}
10      1772    python/pyspark/{sql.py => sql/dataframe.py}
7       6       python/pyspark/{sql_tests.py => sql/tests.py}
8       1465    python/pyspark/{sql.py => sql/types.py}
4       2       python/run-tests
1       1       sql/core/src/main/scala/org/apache/spark/sql/test/ExamplePointUDT.scala
```

Also `git blame -C -C python/pyspark/sql/context.py` to track the history.

Author: Davies Liu <davies@databricks.com>

Closes #4479 from davies/sql and squashes the following commits:

1b5f0a5 [Davies Liu] Merge branch 'master' of github.com:apache/spark into sql
2b2b983 [Davies Liu] restructure pyspark.sql