Mark computed columns as IS_GENERATEDCOLUMN in the result set returne…

…d by getColumns() (#695)

* Fix | getColumns() API, changed column name from SS_IS_COMPUTED to IS_AUTOINCREMENT per JDBC specs | issue #600

* Fix | getColumns() API, changed column name from SS_IS_COMPUTED to IS_GENERATEDCOLUMN per JDBC specs | issue #600

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerDatabaseMetaData.java

@@ -225,7 +225,7 @@ private void checkClosed() throws SQLServerException {
     private static final String FUNCTION_TYPE = "FUNCTION_TYPE";
     private static final String SS_IS_SPARSE = "SS_IS_SPARSE";
     private static final String SS_IS_COLUMN_SET = "SS_IS_COLUMN_SET";
-    private static final String SS_IS_COMPUTED = "SS_IS_COMPUTED";
+    private static final String IS_GENERATEDCOLUMN = "IS_GENERATEDCOLUMN";
     private static final String IS_AUTOINCREMENT = "IS_AUTOINCREMENT";
 
     /**
@@ -565,7 +565,7 @@ private static String EscapeIDName(String inID) throws SQLServerException {
     private static final String[] getColumnsColumnNamesKatmai = {/* 1 */ TABLE_CAT, /* 2 */ TABLE_SCHEM, /* 3 */ TABLE_NAME, /* 4 */ COLUMN_NAME,
             /* 5 */ DATA_TYPE, /* 6 */ TYPE_NAME, /* 7 */ COLUMN_SIZE, /* 8 */ BUFFER_LENGTH, /* 9 */ DECIMAL_DIGITS, /* 10 */ NUM_PREC_RADIX,
             /* 11 */ NULLABLE, /* 12 */ REMARKS, /* 13 */ COLUMN_DEF, /* 14 */ SQL_DATA_TYPE, /* 15 */ SQL_DATETIME_SUB, /* 16 */ CHAR_OCTET_LENGTH,
-            /* 17 */ ORDINAL_POSITION, /* 18 */ IS_NULLABLE, /* 20 */ SS_IS_SPARSE, /* 20 */ SS_IS_COLUMN_SET, /* 21 */ SS_IS_COMPUTED,
+            /* 17 */ ORDINAL_POSITION, /* 18 */ IS_NULLABLE, /* 20 */ SS_IS_SPARSE, /* 20 */ SS_IS_COLUMN_SET, /* 21 */ IS_GENERATEDCOLUMN,
             /* 22 */ IS_AUTOINCREMENT};
 
     /* L0 */ public java.sql.ResultSet getColumns(String catalog,