Fix schema/table escaping with alias in join (#52)

builder/buffer.go

@@ -133,6 +133,9 @@ func (b Buffer) escape(table, value string) string {
 
 	var escaped_table string
 	if table != "" {
+		if i := strings.Index(strings.ToLower(table), " as "); i > -1 {
+			return b.escape(table[:i], "") + " AS " + b.Quoter.ID(table[i+4:])
+		}
 		if b.AllowTableSchema && strings.IndexByte(table, '.') >= 0 {
 			parts := strings.Split(table, ".")
 			for i, part := range parts {

builder/buffer_test.go

@@ -71,6 +71,10 @@ func TestBuffer_escape(t *testing.T) {
 			field:  "person.address as person.address",
 			result: "[person].[address] AS [person.address]",
 		},
+		{
+			table:  "schema.user as primary_user",
+			result: "[schema].[user] AS [primary_user]",
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.result, func(t *testing.T) {