groupby and having getfield index fixes

enginetest/queries/queries.go

@@ -3496,9 +3496,19 @@ Select * from (
 		},
 	},
 	{
-		Query:    `SELECT SUBSTRING_INDEX(mytable.s, "d", 1) AS s FROM mytable INNER JOIN othertable ON (SUBSTRING_INDEX(mytable.s, "d", 1) = SUBSTRING_INDEX(othertable.s2, "d", 1)) GROUP BY 1 HAVING s = 'secon'`,
+		Query:    `SELECT SUBSTRING_INDEX(mytable.s, "d", 1) AS s FROM mytable INNER JOIN othertable ON (SUBSTRING_INDEX(mytable.s, "d", 1) = SUBSTRING_INDEX(othertable.s2, "d", 1)) GROUP BY 1 HAVING s = 'secon';`,
 		Expected: []sql.Row{{"secon"}},
 	},
+	{
+		Query:    `SELECT SUBSTRING_INDEX(mytable.s, "d", 1) AS ss FROM mytable INNER JOIN othertable ON (SUBSTRING_INDEX(mytable.s, "d", 1) = SUBSTRING_INDEX(othertable.s2, "d", 1)) GROUP BY s HAVING s = 'secon';`,
+		Expected: []sql.Row{},
+	},
+	{
+		Query: `SELECT SUBSTRING_INDEX(mytable.s, "d", 1) AS ss FROM mytable INNER JOIN othertable ON (SUBSTRING_INDEX(mytable.s, "d", 1) = SUBSTRING_INDEX(othertable.s2, "d", 1)) GROUP BY ss HAVING ss = 'secon';`,
+		Expected: []sql.Row{
+			{"secon"},
+		},
+	},
 	{
 		Query:    `SELECT TRIM(mytable.s) AS s FROM mytable`,
 		Expected: []sql.Row{{"first row"}, {"second row"}, {"third row"}},

sql/planbuilder/aggregates.go

@@ -775,12 +775,56 @@ func (b *Builder) buildHaving(fromScope, projScope, outScope *scope, having *ast
 	if fromScope.groupBy == nil {
 		fromScope.initGroupBy()
 	}
-	havingScope := fromScope.push()
+	// Having specifies conditions on groups. If not group by is present, all rows implicitly form a single aggregate group.
+	havingScope := fromScope.push() // TODO: we should not be including the entire fromScope
+
 	for _, c := range projScope.cols {
-		if c.tableId.IsEmpty() {
+		// If there are conflicting aliases in the projScope, we prioritize the fromScope
+		found := false
+		for _, cc := range fromScope.cols {
+			if c.col == cc.col {
+				havingScope.addColumn(cc)
+				found = true
+				break
+			}
+		}
+		if found {
+			continue
+		}
+
+		alias, isAlias := c.scalar.(*expression.Alias)
+		if !isAlias {
+			// TODO: error?
+			continue
+		}
+
+		// Aliased GetFields are allowed in having clauses regardless of weather they are in the group by
+		_, isGetField := alias.Child.(*expression.GetField)
+		if isGetField {
+			havingScope.newColumn(c)
+			continue
+		}
+
+		// Aliased expression is allowed if there is no group by (it is implicitly a single group)
+		if len(fromScope.groupBy.inCols) == 0 {
 			havingScope.newColumn(c)
+			continue
+		}
+
+		// Aliased expressions are allowed in having clauses if they are in the group by
+		for _, cc := range fromScope.groupBy.inCols {
+			if c.col == cc.col {
+				havingScope.newColumn(c)
+				found = true
+				break
+			}
+		}
+
+		if found {
+			continue
 		}
 	}
+
 	havingScope.groupBy = fromScope.groupBy
 	h := b.buildScalar(havingScope, having.Expr)
 	outScope.node = plan.NewHaving(h, outScope.node)