[CALCITE-6796] Convert Type from BINARY to VARBINARY in PrestoDialect

core/src/main/java/org/apache/calcite/sql/dialect/PrestoSqlDialect.java

@@ -153,6 +153,10 @@ private static void unparseUsingLimit(SqlWriter writer, @Nullable SqlNode offset
     case FLOAT:
       return new SqlDataTypeSpec(
           new SqlBasicTypeNameSpec(SqlTypeName.DOUBLE, SqlParserPos.ZERO), SqlParserPos.ZERO);
+    // Refer: https://prestodb.io/docs/current/language/types.html#varbinary
+    case BINARY:
+      return new SqlDataTypeSpec(
+          new SqlBasicTypeNameSpec(SqlTypeName.VARBINARY, SqlParserPos.ZERO), SqlParserPos.ZERO);
     default:
       return super.getCastSpec(type);
     }

core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java

@@ -9146,6 +9146,17 @@ private void checkLiteral2(String expression, String expected) {
     sql(query).withOracle().ok(oracle);
   }
 
+  /** Test case for
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-6796">[CALCITE-6796]
+   * Convert Type from BINARY to VARBINARY in PrestoDialect</a>. */
+  @Test void testPrestoBinaryCast() {
+    String query = "SELECT cast(cast(\"employee_id\" as varchar) as binary)"
+        + "from \"foodmart\".\"reserve_employee\" ";
+    String expected = "SELECT CAST(CAST(\"employee_id\" AS VARCHAR) AS VARBINARY)"
+        + "\nFROM \"foodmart\".\"reserve_employee\"";
+    sql(query).withPresto().ok(expected);
+  }
+
   /** Test case for
    * <a href="https://issues.apache.org/jira/browse/CALCITE-6771">[CALCITE-6771]
    * Convert Type from FLOAT to DOUBLE in PrestoDialect</a>. */
@@ -9160,6 +9171,8 @@ private void checkLiteral2(String expression, String expected) {
         .withPresto().ok(expected);
   }
 
+
+
   /** Fluid interface to run tests. */
   static class Sql {
     private final CalciteAssert.SchemaSpec schemaSpec;