Date variable in sqlplus

Having a huge query including several temporal joins and sum over time and several date type binds. I want to execute that query using sqlplus.

SQL> variable til date
Usage: VAR[IABLE] [  [ NUMBER | CHAR | CHAR (n [CHAR|BYTE]) |
                    VARCHAR2 (n [CHAR|BYTE]) | NCHAR | NCHAR (n) |
                    NVARCHAR2 (n) | CLOB | NCLOB | BLOB | BFILE
                    REFCURSOR | BINARY_FLOAT | BINARY_DOUBLE ] ]

Using binds in sqlplus by Tanel Poder and askTom discussing missing date variable support in sqlplus. Putting those together.

SQL> variable fro varchar2(10)
SQL> exec select sysdate into :fro from dual;

PL/SQL procedure successfully completed.

SQL> select 1 from dual where :fro < sysdate;

         1
----------
         1

SQL> print fro

FRO
--------------------------------
13.04.2011

Be aware about possible changes in execution plan caused by datatype conversions. Read the askTom discussion.

Changing NLS_DATE_FORMAT

SQL> alter session set nls_territory=america;

Session altered.

SQL> select 1 from dual where :fro < sysdate;
select 1 from dual where :fro < sysdate
                          *
ERROR at line 1:
ORA-01843: not a valid month


SQL> exec select sysdate into :fro from dual;

PL/SQL procedure successfully completed.

SQL> select 1 from dual where :fro < sysdate;

         1
----------
         1

SQL> print fro

FRO
--------------------------------
13-APR-11

And yet another aspect about date formats

SQL> select 1 from dual where :fro = trunc(sysdate);

         1
----------
         1

SQL> alter session set nls_date_format='yyyymmdd hh24mi';

Session altered.

SQL> exec select sysdate into :fro from dual;
BEGIN select sysdate into :fro from dual; END;

*
ERROR at line 1:
ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at line 1


SQL> variable fro varchar2(13)
SQL> exec select sysdate into :fro from dual;

PL/SQL procedure successfully completed.

SQL> select 1 from dual where :fro = trunc(sysdate);

no rows selected

SQL> print fro

FRO
--------------------------------
20110413 0902

11.2 XE beta and SQL Developer 3

11.2 XE beta available.

And seems like not a april fool Tanel Poder describing features.

Documentation available. And a dedicated discussion forum.

SQL Deveoper 3 beta days seems to be over

Descending index is function based

Descendin index is implemented as function based index in Oracle. This is documented and discussed.
Nulls may lead to a surprise with a desc unique index.

SQL> create table a(a varchar2(2 char), b varchar2(2 char) );

Table created.

SQL>
SQL> select table_name,column_name,data_type,data_length from user_tab_cols where table_name = 'A';

TABLE_NAME                     COLUMN_NAME                    DATA_TYPE
------------------------------ ------------------------------ --------------------------------------
A                              A                              VARCHAR2
A                              B                              VARCHAR2

SQL>
SQL> create unique index a_idx on a (a,b desc);

Index created.

SQL>
SQL> select table_name,column_name,data_type,data_length from user_tab_cols where table_name = 'A';

TABLE_NAME                     COLUMN_NAME                    DATA_TYPE
------------------------------ ------------------------------ --------------------------------------
A                              A                              VARCHAR2
A                              B                              VARCHAR2
A                              SYS_NC00003$                   RAW

SQL>
SQL> select index_type from user_indexes where index_name = 'A_IDX';

INDEX_TYPE
---------------------------
FUNCTION-BASED NORMAL

SQL>
SQL> select * from user_ind_columns where index_name = 'A_IDX';

INDEX_NAME                     TABLE_NAME
------------------------------ ------------------------------
COLUMN_NAME
----------------------------------------------------------------------------------------------------
COLUMN_POSITION COLUMN_LENGTH CHAR_LENGTH DESC
--------------- ------------- ----------- ----
A_IDX                          A
A
              1             8           2 ASC

A_IDX                          A
SYS_NC00003$
              2            13           0 DESC


SQL>
SQL> select * from USER_IND_EXPRESSIONS where index_name = 'A_IDX';

INDEX_NAME                     TABLE_NAME                     COLUMN_EXPRESSION
------------------------------ ------------------------------ --------------------------------------
A_IDX                          A                              "B"

SQL>
SQL> insert into a values(null,null);

1 row created.

SQL>
SQL> insert into a values(null,null);
insert into a values(null,null)
*
ERROR at line 1:
ORA-00001: unique constraint (KIOS.A_IDX) violated


SQL>
SQL> drop index a_idx;

Index dropped.

SQL>
SQL> create unique index a_idx on a (a,b);

Index created.

SQL>
SQL> insert into a values(null,null);

1 row created.

SQL>
SQL> insert into a values(null,null);

1 row created.

Installing

Just to remember. Have to try next time when installing a new computer.
http://ninite.com