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[SPARK-25196][SQL] Extends the analyze column command for cached tables
## What changes were proposed in this pull request?
This pr extended `ANALYZE` commands to analyze column stats for cached table.
In common use cases, users read catalog table data, join/aggregate them, and then cache the result for following reuse. Since we are only allowed to analyze column statistics in catalog tables via ANALYZE commands, the current optimization depends on non-existing or inaccurate column statistics of cached data. So, it would be great if we could analyze cached data as follows;
```scala
scala> def printColumnStats(tableName: String) = {
| spark.table(tableName).queryExecution.optimizedPlan.stats.attributeStats.foreach {
| case (k, v) => println(s"[$k]: $v")
| }
| }
scala> sql("SET spark.sql.cbo.enabled=true")
scala> sql("SET spark.sql.statistics.histogram.enabled=true")
scala> spark.range(1000).selectExpr("id % 33 AS c0", "rand() AS c1", "0 AS c2").write.saveAsTable("t")
scala> sql("ANALYZE TABLE t COMPUTE STATISTICS FOR COLUMNS c0, c1, c2")
scala> spark.table("t").groupBy("c0").agg(count("c1").as("v1"), sum("c2").as("v2")).createTempView("temp")
// Prints column statistics in catalog table `t`
scala> printColumnStats("t")
[c0#7073L]: ColumnStat(Some(33),Some(0),Some(32),Some(0),Some(8),Some(8),Some(Histogram(3.937007874015748,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;9f7c1c)),2)
[c1#7074]: ColumnStat(Some(944),Some(3.2108484832404915E-4),Some(0.997584797423909),Some(0),Some(8),Some(8),Some(Histogram(3.937007874015748,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;60a386b1)),2)
[c2#7075]: ColumnStat(Some(1),Some(0),Some(0),Some(0),Some(4),Some(4),Some(Histogram(3.937007874015748,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;5ffd29e8)),2)
// Prints column statistics on cached table `temp`
scala> sql("CACHE TABLE temp")
scala> printColumnStats("temp")
<No Column Statistics>
// Analyzes columns `v1` and `v2` on cached table `temp`
scala> sql("ANALYZE TABLE temp COMPUTE STATISTICS FOR COLUMNS v1, v2")
// Then, prints again
scala> printColumnStats("temp")
[v1#7084L]: ColumnStat(Some(2),Some(30),Some(31),Some(0),Some(8),Some(8),Some(Histogram(0.12992125984251968,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;49f7bb6f)),2)
[v2#7086L]: ColumnStat(Some(1),Some(0),Some(0),Some(0),Some(8),Some(8),Some(Histogram(0.12992125984251968,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;12701677)),2)
// Analyzes one left column and prints again
scala> sql("ANALYZE TABLE temp COMPUTE STATISTICS FOR COLUMNS c0")
scala> printColumnStats("temp")
[v1#7084L]: ColumnStat(Some(2),Some(30),Some(31),Some(0),Some(8),Some(8),Some(Histogram(0.12992125984251968,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;49f7bb6f)),2)
[v2#7086L]: ColumnStat(Some(1),Some(0),Some(0),Some(0),Some(8),Some(8),Some(Histogram(0.12992125984251968,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;12701677)),2)
[c0#7073L]: ColumnStat(Some(33),Some(0),Some(32),Some(0),Some(8),Some(8),Some(Histogram(0.12992125984251968,[Lorg.apache.spark.sql.catalyst.plans.logical.HistogramBin;1f5c1b81)),2)
```
## How was this patch tested?
Added tests in `CachedTableSuite` and `StatisticsCollectionSuite`.
Closesapache#24047 from maropu/SPARK-25196-4.
Authored-by: Takeshi Yamamuro <[email protected]>
Signed-off-by: Dongjoon Hyun <[email protected]>
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