ORA-00900: invalid SQL statement

I got ” ORA-00900: invalid SQL statement ”  error in Oracle database.

ORA-00900: invalid SQL statement

Details of error are as follows.

ORA-00900 invalid SQL statement
Cause: The statement is not recognized as a valid SQL statement. This error can occur if the
 Procedural Option is not installed and a SQL statement is issued that requires this option 
(for example, a CREATE PROCEDURE statement). You can determine if the Procedural Option is
 installed by starting SQL*Plus. If the PL/SQL banner is not displayed, then the option is not installed.

Action: Correct the syntax or install the Procedural Option.

invalid SQL statement

This ORA-00900 error is related with the statement is not recognized as a valid SQL statement. This error can occur if the Procedural Option is not installed and a SQL statement is issued that requires this option (for example, a CREATE PROCEDURE statement). You can determine if the Procedural Option is installed by starting SQL*Plus. If the PL/SQL banner is not displayed, then the option is not installed.

Correct the syntax or install the Procedural Option.

To solve this error, you need to use nls_date_format as follows.

alter session nls_date_format='DD/MM/YYYY HH:MM:SS AM';

Or use the TO_DATE function as follows.

insert into test values (TO_DATE('2008-12-23T17:28:44','YYYY-MM-DD"T"HH24:MI:SS'));

OR

EXECUTE IMMEDIATE failed when calling PL/SQL object:

SQL>  set serveroutput on
SQL>  declare
  2   v_sql_cmd varchar2(1100);
  3   v_userid varchar2(10):='scott';
  4    v_TEMP_PASSWORD varchar2(10):='testuser';
  5   begin
  6     v_sql_cmd := 'DBMS_UTILITY.EXEC_DDL_STATEMENT(''alter user '|| v_userid|| ' identified by '|| v_TEMP_PASSWORD|| ' password expire'')';
  7              DBMS_OUTPUT.put_line (v_sql_cmd);
  8             execute immediate v_sql_cmd;
  9  end;
 10  /
DBMS_UTILITY.EXEC_DDL_STATEMENT('alter user testuser identified by testuser
password expire')
 declare
*
ERROR at line 1:
ORA-00900: invalid SQL statement
ORA-06512: at line 8

SQL>  declare
  2   v_sql_cmd varchar2(1100);
  3   v_userid varchar2(10):='scott';
  4    v_TEMP_PASSWORD varchar2(10):='tiger';
  5   begin
  6     v_sql_cmd := 'BEGIN DBMS_UTILITY.EXEC_DDL_STATEMENT(''alter user '|| v_userid|| ' identified by '|| v_TEMP_PASSWORD|| ' password expire''); END;';
  7              DBMS_OUTPUT.put_line (v_sql_cmd);
  8             execute immediate v_sql_cmd;
  9  end;
 10  /
BEGIN DBMS_UTILITY.EXEC_DDL_STATEMENT('alter user testuser identified by tiger
password expire'); END;

PL/SQL procedure successfully completed.

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