spark-instrumented-optimizer/sql
hyukjinkwon 86c2d393a5
[SPARK-17480][SQL][FOLLOWUP] Fix more instances which calls List.length/size which is O(n)
## What changes were proposed in this pull request?

This PR fixes all the instances which was fixed in the previous PR.

To make sure, I manually debugged and also checked the Scala source. `length` in [LinearSeqOptimized.scala#L49-L57](https://github.com/scala/scala/blob/2.11.x/src/library/scala/collection/LinearSeqOptimized.scala#L49-L57) is O(n). Also, `size` calls `length` via [SeqLike.scala#L106](https://github.com/scala/scala/blob/2.11.x/src/library/scala/collection/SeqLike.scala#L106).

For debugging, I have created these as below:

```scala
ArrayBuffer(1, 2, 3)
Array(1, 2, 3)
List(1, 2, 3)
Seq(1, 2, 3)
```

and then called `size` and `length` for each to debug.

## How was this patch tested?

I ran the bash as below on Mac

```bash
find . -name *.scala -type f -exec grep -il "while (.*\\.length)" {} \; | grep "src/main"
find . -name *.scala -type f -exec grep -il "while (.*\\.size)" {} \; | grep "src/main"
```

and then checked each.

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #15093 from HyukjinKwon/SPARK-17480-followup.
2016-09-17 16:52:30 +01:00
..
catalyst [SPARK-17480][SQL][FOLLOWUP] Fix more instances which calls List.length/size which is O(n) 2016-09-17 16:52:30 +01:00
core [SPARK-17480][SQL][FOLLOWUP] Fix more instances which calls List.length/size which is O(n) 2016-09-17 16:52:30 +01:00
hive [SPARK-17480][SQL][FOLLOWUP] Fix more instances which calls List.length/size which is O(n) 2016-09-17 16:52:30 +01:00
hive-thriftserver [SPARK-17190][SQL] Removal of HiveSharedState 2016-08-25 12:50:03 +08:00
README.md [SPARK-16557][SQL] Remove stale doc in sql/README.md 2016-07-14 19:24:42 -07:00

Spark SQL

This module provides support for executing relational queries expressed in either SQL or the DataFrame/Dataset API.

Spark SQL is broken up into four subprojects:

  • Catalyst (sql/catalyst) - An implementation-agnostic framework for manipulating trees of relational operators and expressions.
  • Execution (sql/core) - A query planner / execution engine for translating Catalyst's logical query plans into Spark RDDs. This component also includes a new public interface, SQLContext, that allows users to execute SQL or LINQ statements against existing RDDs and Parquet files.
  • Hive Support (sql/hive) - Includes an extension of SQLContext called HiveContext that allows users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allows users to run queries that include Hive UDFs, UDAFs, and UDTFs.
  • HiveServer and CLI support (sql/hive-thriftserver) - Includes support for the SQL CLI (bin/spark-sql) and a HiveServer2 (for JDBC/ODBC) compatible server.