SQL: Proper errors on set qualifiers (elastic/x-pack-elasticsearch#3377)

`SELECT DISTINCT foo FROM bar` is not yet implemented and was returning
an "unplanned item" error which isn't useful to users so I replaced it
with `SELECT DISTINCT is not yet supported`.

`SELECT foo, COUNT(*) FROM bar GROUP BY ALL foo` is not supported.
Specifically the `ALL` part. It is fairly esoteric so see [1] for what
it does. Regardless of what it does it is not widely supported and even
Microsoft's SQL Server has deprecated it so we should never support it.
Probably.

[1]: https://technet.microsoft.com/en-us/library/ms175028(v=sql.90).aspx

Related to elastic/x-pack-elasticsearch#3176

Original commit: elastic/x-pack-elasticsearch@56e5ca3009

qa/sql/src/main/java/org/elasticsearch/xpack/qa/sql/rest/RestSqlTestCase.java

@@ -162,6 +162,18 @@ public abstract class RestSqlTestCase extends ESRestTestCase implements ErrorsTe
             containsString("line 1:67: Queries with JOIN are not yet supported"));
     }
 
+    public void testSelectDistinctFails() throws Exception {
+        index("{\"name\":\"test\"}");
+        expectBadRequest(() -> runSql("SELECT DISTINCT name FROM test"),
+            containsString("line 1:8: SELECT DISTINCT is not yet supported"));
+    }
+
+    public void testSelectGroupByAllFails() throws Exception {
+        index("{\"foo\":1}", "{\"foo\":2}");
+        expectBadRequest(() -> runSql("SELECT foo FROM test GROUP BY ALL foo"),
+            containsString("line 1:32: GROUP BY ALL is not supported"));
+    }
+
     @Override
     public void testSelectInvalidSql() {
         expectBadRequest(() -> runSql("SELECT * FRO"), containsString("1:8: Cannot determine columns for *"));

sql/server/src/main/java/org/elasticsearch/xpack/sql/analysis/analyzer/Verifier.java

@@ -18,6 +18,7 @@ import org.elasticsearch.xpack.sql.expression.function.Functions;
 import org.elasticsearch.xpack.sql.expression.function.Score;
 import org.elasticsearch.xpack.sql.expression.function.scalar.ScalarFunction;
 import org.elasticsearch.xpack.sql.plan.logical.Aggregate;
+import org.elasticsearch.xpack.sql.plan.logical.Distinct;
 import org.elasticsearch.xpack.sql.plan.logical.Filter;
 import org.elasticsearch.xpack.sql.plan.logical.LogicalPlan;
 import org.elasticsearch.xpack.sql.plan.logical.OrderBy;
@@ -107,8 +108,9 @@ abstract class Verifier {
 
             if (p instanceof Unresolvable) {
                 localFailures.add(fail(p, ((Unresolvable) p).unresolvedMessage()));
-            }
+            } else if (p instanceof Distinct) {
-            else {
+                localFailures.add(fail(p, "SELECT DISTINCT is not yet supported"));
+            } else {
                 // then take a look at the expressions
                 p.forEachExpressions(e -> {
                     // everything is fine, skip expression

sql/server/src/main/java/org/elasticsearch/xpack/sql/parser/LogicalPlanBuilder.java

@@ -5,6 +5,7 @@
  */
 package org.elasticsearch.xpack.sql.parser;
 
+import org.antlr.v4.runtime.tree.TerminalNode;
 import org.elasticsearch.xpack.sql.expression.Expression;
 import org.elasticsearch.xpack.sql.expression.Literal;
 import org.elasticsearch.xpack.sql.expression.NamedExpression;
@@ -13,6 +14,7 @@ import org.elasticsearch.xpack.sql.expression.UnresolvedAlias;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.AliasedQueryContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.AliasedRelationContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.FromClauseContext;
+import org.elasticsearch.xpack.sql.parser.SqlBaseParser.GroupByContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.JoinCriteriaContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.JoinRelationContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.JoinTypeContext;
@@ -21,6 +23,7 @@ import org.elasticsearch.xpack.sql.parser.SqlBaseParser.QueryContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.QueryNoWithContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.QuerySpecificationContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.RelationContext;
+import org.elasticsearch.xpack.sql.parser.SqlBaseParser.SetQuantifierContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.SubqueryContext;
 import org.elasticsearch.xpack.sql.parser.SqlBaseParser.TableNameContext;
 import org.elasticsearch.xpack.sql.plan.TableIdentifier;
@@ -109,9 +112,15 @@ abstract class LogicalPlanBuilder extends ExpressionBuilder {
         }
 
         // GROUP BY
-        if (ctx.groupBy() != null) {
+        GroupByContext groupByCtx = ctx.groupBy();
-            List<Expression> groupBy = expressions(ctx.groupBy().groupingElement());
+        if (groupByCtx != null) {
-            query = new Aggregate(source(ctx.groupBy()), query, groupBy, selectTarget);
+            SetQuantifierContext setQualifierContext = groupByCtx.setQuantifier();
+            TerminalNode groupByAll = setQualifierContext == null ? null : setQualifierContext.ALL();
+            if (groupByAll != null) {
+                throw new ParsingException(source(groupByAll), "GROUP BY ALL is not supported");
+            }
+            List<Expression> groupBy = expressions(groupByCtx.groupingElement());
+            query = new Aggregate(source(groupByCtx), query, groupBy, selectTarget);
         }
         else if (!selectTarget.isEmpty()) {
             query = new Project(source(ctx.selectItem(0)), query, selectTarget);