EBCDIC CCSID field (SCCSID, MCCSID, and GCCSID DECP values)

The value of the EBCDIC CCSID field specifies the default CCSID for EBCDIC-encoded character data that is stored in your Db2 subsystem or data sharing system.

Db2 uses this value to perform conversion of character data that is received from external sources including other database management systems. Choose this value carefully to avoid loss of data integrity. The values that you choose for EBCDIC CCSID and ASCII CCSID are closely related.

Acceptable values: 1 - 65533
Default: (none)
Update: not recommended; data integrity may be compromised
dsnhdecp: SCCSID (single-byte), MCCSID (mixed), GCCSID (graphic)

If you specify NO for the MIXED DATA field, the MCCSID and GCCSID values are 65534. If you specify YES for the MIXED DATA field, ensure that you use the correct single-byte CCSID and MCCSID.

Recommendation: Use this parameter to specify an MCCSID. By doing so, you also receive system CCSIDs for your SBCS and GRAPHIC data. If you edit DSNHDECP directly, you will not receive the system CCSIDs for your SBCS and GRAPHIC data.

Conversions are determined in the following order:

  1. SYSIBM.SYSSTRINGS.
  2. z/OS® Unicode conversion services.

Considerations for mixed data:

  • If the MIXED DATA field is set to YES, you must specify a MCCSID from EBCDIC and ASCII support. An error occurs if you do not specify a CCSID or if the CCSID you specify is not listed in the table.
  • If you specify 930, 1390, or 5026, Katakana characters are allowed in ordinary identifiers, and letters are not changed to uppercase.

If you specify a CCSID that is recognized by Db2 but is inappropriate for your site, data might be corrupted. For example, assume that the coded character set at your site is 37, but you specify 500 as the system CCSID. If Db2 receives data with a CCSID of 37, the data might be corrupted because character conversion does not occur. Conversely, if Db2 receives data with a CCSID other than 500 and a conversion is made from that CCSID to 500, the data may be corrupted because character conversion does occur.

Altering CCSIDs can be very disruptive to a system. Converting to a CCSID that supports the euro symbol is potentially less disruptive because specific pre-euro CCSIDs map to specific CCSIDs for the euro. Converting to a different CCSID for other reasons, particularly when a Db2 system has been operating with the wrong CCSID, could render data unusable and unrecoverable.

Recommendation: Never change CCSIDs on an existing Db2 system without specific guidance from IBM® Software Support.