From 3a12ab114dd70ad3690fa9382b7ecb6e7caeffe8 Mon Sep 17 00:00:00 2001
From: kasiafi <30203062+kasiafi@users.noreply.github.com>
Date: Sat, 11 May 2019 17:21:17 +0200
Subject: [PATCH] Allow simplified OFFSET syntax

This change allows using simplified syntax
`OFFSET x`
instead of
`OFFSET x ROW/ROWS`
---
 .../antlr4/io/prestosql/sql/parser/SqlBase.g4 |  2 +-
 .../prestosql/sql/parser/TestSqlParser.java   | 26 +++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/presto-parser/src/main/antlr4/io/prestosql/sql/parser/SqlBase.g4 b/presto-parser/src/main/antlr4/io/prestosql/sql/parser/SqlBase.g4
index 416d1fe1cdbf..d588d18c902d 100644
--- a/presto-parser/src/main/antlr4/io/prestosql/sql/parser/SqlBase.g4
+++ b/presto-parser/src/main/antlr4/io/prestosql/sql/parser/SqlBase.g4
@@ -149,7 +149,7 @@ property
 queryNoWith:
       queryTerm
       (ORDER BY sortItem (',' sortItem)*)?
-      (OFFSET offset=INTEGER_VALUE (ROW | ROWS))?
+      (OFFSET offset=INTEGER_VALUE (ROW | ROWS)?)?
       ((LIMIT limit=(INTEGER_VALUE | ALL)) | (FETCH (FIRST | NEXT) (fetchFirst=INTEGER_VALUE)? (ROW | ROWS) ONLY))?
     ;
 
diff --git a/presto-parser/src/test/java/io/prestosql/sql/parser/TestSqlParser.java b/presto-parser/src/test/java/io/prestosql/sql/parser/TestSqlParser.java
index e47800ca19b7..79406df48afa 100644
--- a/presto-parser/src/test/java/io/prestosql/sql/parser/TestSqlParser.java
+++ b/presto-parser/src/test/java/io/prestosql/sql/parser/TestSqlParser.java
@@ -946,6 +946,22 @@ public void testSelectWithOffset()
                         Optional.empty(),
                         Optional.empty()));
 
+        assertStatement("SELECT * FROM table1 OFFSET 2",
+                new Query(
+                        Optional.empty(),
+                        new QuerySpecification(
+                                selectList(new AllColumns()),
+                                Optional.of(new Table(QualifiedName.of("table1"))),
+                                Optional.empty(),
+                                Optional.empty(),
+                                Optional.empty(),
+                                Optional.empty(),
+                                Optional.of(new Offset("2")),
+                                Optional.empty()),
+                        Optional.empty(),
+                        Optional.empty(),
+                        Optional.empty()));
+
         Query valuesQuery = query(values(
                 row(new LongLiteral("1"), new StringLiteral("1")),
                 row(new LongLiteral("2"), new StringLiteral("2"))));
@@ -959,6 +975,16 @@ public void testSelectWithOffset()
                         Optional.empty(),
                         Optional.of(new Offset("2")),
                         Optional.empty()));
+
+        assertStatement("SELECT * FROM (VALUES (1, '1'), (2, '2')) OFFSET 2",
+                simpleQuery(selectList(new AllColumns()),
+                        subquery(valuesQuery),
+                        Optional.empty(),
+                        Optional.empty(),
+                        Optional.empty(),
+                        Optional.empty(),
+                        Optional.of(new Offset("2")),
+                        Optional.empty()));
     }
 
     @Test