fix: update db2 select grammar as per doc

update db2 select grammar as per https://www.ibm.com/docs/en/db2/11.5?topic=queries-select-statement

Signed-off-by: Aman Prashant <[email protected]>

Author: ap891843

server/engine/src/main/antlr4/org/eclipse/lsp/cobol/core/parser/Db2SqlParser.g4

@@ -881,15 +881,19 @@ dbs_savepoint: SAVEPOINT dbs_savepoint_name UNIQUE? ON ROLLBACK RETAIN (CURSORS
 
 
 dbs_select: dbs_select_unpack_function_invocation | (WITH common_table_expression_loop)? dbs_fullselect
-            (dbs_select_update
+            ( dbs_select_update
              | dbs_select_readOnly
              | dbs_select_optimize
              | dbs_select_statement_isolation_clause
-             | (QUERYNO dbs_integer)
-             | (SKIPCHAR LOCKED DATA))*;
+             | dbs_concurrent_access_resolution_clause
+             | dbs_offset_clause
+             | dbs_fetch_clause
+             | dbs_lock_req_clause )*;
 dbs_select_update: FOR UPDATE (OF dbs_column_name (dbs_comma_separator dbs_column_name)*)? ;
-dbs_select_readOnly: FOR READ ONLY;
+dbs_select_readOnly: FOR (READ | FETCH) ONLY;
 dbs_select_optimize:OPTIMIZE FOR dbs_integer (ROWS | ROW);
+dbs_concurrent_access_resolution_clause: (WAIT FOR OUTCOME) | (SKIPCHAR LOCKED DATA) ;
+dbs_lock_req_clause: USE AND KEEP (SHARE| UPDATE | EXCLUSIVE) LOCKS;
 /*Queries Subselects (all)*/
 dbs_select_unpack_function_invocation: UNPACK LPARENCHAR dbs_expression RPARENCHAR DOT_FS ASTERISKCHAR AS LPARENCHAR dbs_field_name db2sql_data_types (dbs_comma_separator dbs_field_name db2sql_data_types)* RPARENCHAR;
 dbs_select_row_fullselect: (NONNUMERICLITERAL | NUMERICLITERAL)+ ;

server/engine/src/test/java/org/eclipse/lsp/cobol/usecases/TestSqlSelectStatement.java

@@ -139,9 +139,16 @@ class TestSqlSelectStatement {
           + "            FROM SYSIBM.SYSDUMMY1                                       00095700\n"
           + "           END-EXEC.                                                    00095800";
 
+  private static final String SELECT14 =
+          TEXT
+                  + "            DECLARE C1 CURSOR FOR \n"
+                  + "             SELECT * FROM RMTTAB\n"
+                  + "               FOR FETCH ONLY \n"
+                  + "           END-EXEC.\n";
+
   private static Stream<String> textsToTest() {
     return Stream.of(SELECT, SELECT2, SELECT3, SELECT4, SELECT5, SELECT6, SELECT7, SELECT8, SELECT9, SELECT10,
-            SELECT11, SELECT12, SELECT13);
+            SELECT11, SELECT12, SELECT13, SELECT14);
   }
 
   @ParameterizedTest