[SPARK-1998] SparkFlumeEvent with body bigger than 1020 bytes are not re...

flume event sent to Spark will fail if the body is too large and numHeaders is greater than zero

Author: joyyoj <sunshch@gmail.com>

Closes #951 from joyyoj/master and squashes the following commits:

f4660c5 [joyyoj] [SPARK-1998] SparkFlumeEvent with body bigger than 1020 bytes are not read properly
(cherry picked from commit 29660443077619ee854025b8d0d3d64181724054)

Signed-off-by: Patrick Wendell <pwendell@gmail.com>
HOTFIX: clear() configs in SQLConf-related unit tests.

Thanks goes to @liancheng, who pointed out that `sql/test-only *.SQLConfSuite *.SQLQuerySuite` passed but `sql/test-only *.SQLQuerySuite *.SQLConfSuite` failed. The reason is that some tests use the same test keys and without clear()'ing, they get carried over to other tests. This hotfix simply adds some `clear()` calls.

This problem was not evident on Jenkins before probably because `parallelExecution` is not set to `false` for `sqlCoreSettings`.

Author: Zongheng Yang <zongheng.y@gmail.com>

Closes #1040 from concretevitamin/sqlconf-tests and squashes the following commits:

6d14ceb [Zongheng Yang] HOTFIX: clear() confs in SQLConf related unit tests.

(cherry picked from commit 601032f5bfe2dcdc240bfcc553f401e6facbf5ec)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-2093] [SQL] NullPropagation should use exact type value.

`NullPropagation` should use exact type value when transform `Count` or `Sum`.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #1034 from ueshin/issues/SPARK-2093 and squashes the following commits:

65b6ff1 [Takuya UESHIN] Modify the literal value of the result of transformation from Sum to long value.
830c20b [Takuya UESHIN] Add Cast to the result of transformation from Count.
9314806 [Takuya UESHIN] Fix NullPropagation to use exact type value.

(cherry picked from commit 0402bd77ec786d1fa6cfd7f9cc3aa97c7ab16fd8)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-1968][SQL] SQL/HiveQL command for caching/uncaching tables

JIRA issue: [SPARK-1968](https://issues.apache.org/jira/browse/SPARK-1968)

This PR added support for SQL/HiveQL command for caching/uncaching tables:

```
scala> sql("CACHE TABLE src")
...
res0: org.apache.spark.sql.SchemaRDD =
SchemaRDD[0] at RDD at SchemaRDD.scala:98
== Query Plan ==
CacheCommandPhysical src, true

scala> table("src")
...
res1: org.apache.spark.sql.SchemaRDD =
SchemaRDD[3] at RDD at SchemaRDD.scala:98
== Query Plan ==
InMemoryColumnarTableScan [key#0,value#1], (HiveTableScan [key#0,value#1], (MetastoreRelation default, src, None), None), false

scala> isCached("src")
res2: Boolean = true

scala> sql("CACHE TABLE src")
...
res3: org.apache.spark.sql.SchemaRDD =
SchemaRDD[4] at RDD at SchemaRDD.scala:98
== Query Plan ==
CacheCommandPhysical src, false

scala> table("src")
...
res4: org.apache.spark.sql.SchemaRDD =
SchemaRDD[11] at RDD at SchemaRDD.scala:98
== Query Plan ==
HiveTableScan [key#2,value#3], (MetastoreRelation default, src, None), None

scala> isCached("src")
res5: Boolean = false
```

Things also work for `hql`.

Author: Cheng Lian <lian.cs.zju@gmail.com>

Closes #1038 from liancheng/sqlCacheTable and squashes the following commits:

ecb7194 [Cheng Lian] Trimmed the SQL string before parsing special commands
6f4ce42 [Cheng Lian] Moved logical command classes to a separate file
3458a24 [Cheng Lian] Added comment for public API
f0ffacc [Cheng Lian] Added isCached() predicate
15ec6d2 [Cheng Lian] Added "(UN)CACHE TABLE" SQL/HiveQL statements

(cherry picked from commit 0266a0c8a70e0fbaeb0df63031f7a750ffc31a80)
Signed-off-by: Michael Armbrust <michael@databricks.com>
SPARK-2107: FilterPushdownSuite doesn't need Junit jar.

Author: Qiuzhuang.Lian <Qiuzhuang.Lian@gmail.com>

Closes #1046 from Qiuzhuang/master and squashes the following commits:

0a9921a [Qiuzhuang.Lian] SPARK-2107: FilterPushdownSuite doesn't need Junit jar.