2.10 Known Problems
This section describes known problems and includes suggestions for correcting them when possible for Oracle Database Gateway for Sybase.
If you have any questions or concerns about the problems, contact Oracle Support Services. A current list of problems is available online. Contact your local Oracle office for information about accessing the list.
The known problems are as follows:
- Encrypted Format Login
Oracle database no longer supports the initialization parameterDBLINK_ENCRYPT_LOGIN
. - Date Arithmetic
Oracle Database Gateway for Sybase does not support some date arithmetic functions. - Sybase IMAGE and TEXT Data Type
There are restrictions when usingIMAGE
andTEXT
data types with Oracle Database Gateway for Sybase. - String Functions
If you concatenate numeric literals using the "||
" operator when using the gateway to query a Sybase database, the result is an arithmetic addition. - Schema Names and PL/SQL
If you do not prefix a Sybase database object with its schema name in a SQL statement within a PL/SQL block, an error is returned. - Data Dictionary Views and PL/SQL
You cannot refer to data dictionary views in SQL statements that are inside a PL/SQL block. - Stored Procedures
Return values of stored procedures that return result sets are incorrect.
Parent topic: Sybase Gateway Features and Restrictions
2.10.1 Encrypted Format Login
Oracle database no longer supports the initialization parameter DBLINK_ENCRYPT_LOGIN
.
Up to version 7.3, this parameter's default TRUE value prevented the password for the login user ID from being sent over the network (in the clear). Later versions automatically encrypt the password.
Parent topic: Known Problems
2.10.2 Date Arithmetic
Oracle Database Gateway for Sybase does not support some date arithmetic functions.
The following SQL expressions do not function correctly with the gateway:
date + numbernumber + datedate - numberdate1 - date2
Statements with the preceding expressions are sent to the Sybase database without any translation. Since Sybase does not support these date arithmetic functions, the statements return an error.
Parent topic: Known Problems
2.10.3 Sybase IMAGE and TEXT Data Type
There are restrictions when using IMAGE
and TEXT
data types with Oracle Database Gateway for Sybase.
The following restrictions apply when using IMAGE
and TEXT
data types:
-
An unsupported SQL function cannot be used in a SQL statement that accesses a column defined as Sybase data type
IMAGE
orTEXT
. -
You cannot use SQL*Plus to select data from a column defined as Sybase data type
IMAGE
orTEXT
when the data is greater than 80 characters in length. Oracle recommends using Pro*C or Oracle Call Interface to access such data in a Sybase database. -
IMAGE
andTEXT
data cannot be read through pass-through queries.
The gateway does not support the PL/SQL function COLUMN_VALUE_LONG
of the DBMS_SQL
package.
See Also:
Supported SQL Syntax and Functions for more information about restrictions on SQL syntax.Parent topic: Known Problems
2.10.4 String Functions
If you concatenate numeric literals using the "||
" operator when using the gateway to query a Sybase database, the result is an arithmetic addition.
For example, the result of the following statement is 18:
SQL> SELECT 9 || 9 FROM DUAL@SYBS;
The result is 99
when using Oracle to query an Oracle database.
Parent topic: Known Problems
2.10.5 Schema Names and PL/SQL
If you do not prefix a Sybase database object with its schema name in a SQL statement within a PL/SQL block, an error is returned.
For example:
ORA-6550 PLS-201 Identifier table_name must be declared.
Change the SQL statement to include the schema name of the object.
Parent topic: Known Problems
2.10.6 Data Dictionary Views and PL/SQL
You cannot refer to data dictionary views in SQL statements that are inside a PL/SQL block.
Parent topic: Known Problems
2.10.7 Stored Procedures
Return values of stored procedures that return result sets are incorrect.
Parent topic: Known Problems