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ANSI/ISO, DB2, and SQL/DS Datatypes

Accessing Oracle Database Version 7 from an Oracle9i Client The ROWID values that are returned are always restricted ROWIDs. Also, Oracle9i returns restricted ROWID values to a database server for Oracle Database version 7.

The following ROWID functionality works when accessing a server for Oracle Database version 7:

Selecting a ROWID and using the obtained value in a WHERE clause

WHERE CURRENT OF cursor operations

Storing ROWIDs in user columns of ROWID or CHAR type

Interpreting ROWIDs using the hexadecimal encoding (not recommended – use the DBMS_ROWID functions)

Accessing an Oracle9i Database from a Client of Oracle Database Version 7 Oracle9i returns

ROWIDs in the extended format. This means that you can only:

Select a ROWID and use it in a WHERE clause

Use WHERE CURRENT OF cursor operations

Store ROWIDs in user columns of CHAR(18) datatype

Import and Export It is not possible for a client of Oracle Database version 7 to import a table from a later version that has a ROWID column (not the ROWID pseudocolumn), if any row of the table contains an extended ROWID value.

ANSI/ISO, DB2, and SQL/DS Datatypes

You can define columns of tables in Oracle Database using ANSI/ISO, DB2, and SQL/DS datatypes. Oracle Database internally converts such datatypes to Oracle datatypes.

The ANSI datatype conversions are shown in Table 2–7. The ANSI/ISO datatypes NUMERIC, DECIMAL, and DEC can specify only fixed-point numbers. For these datatypes, s defaults to 0.

Table 2–7 ANSI Datatype Conversions to Oracle Datatypes

ANSI SQL Datatype

Oracle Datatype

 

 

 

CHARACTER (n),

CHAR (n)

CHAR (n)

NUMERIC (p,s),

DECIMAL (p,s), DEC (p,s)

NUMBER (p,s)

Selecting a Datatype 2-39

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