The character set on the database named TCHEBCDIC937_3IB is intended as an extended EBCDIC character set consisting of both one and two-bytes per character. Architecturally, the EBCDIC encoding scheme consists of 256 possible values (codepoints) represented as hexadecimal values in the range X'00' to X'FF'
To support more than 256 codepoints, the EBCDIC encoding scheme is extended by defining the Shift-out control character to switch from one byte per character to two bytes per character until the Shift-in control character is encountered. The first byte of codepoints between the Shift-out and Shift-in control characters is always between X'41' and X'FE'. Currently, the second byte is also between X'41' and X'FE'. The X'4040' codepoint is defined as the Double-byte Space character. No double-byte control characters exist. The double-byte characters are not described.
|Control character codepoints|
The database rejects character data containing any single or double byte reserved codepoint and does not identify which invalid codepoint was present.
Graphic characters do not correspond to a known IBM codepage (given its CCSID of 00937, the single-byte codepage should be 00037). The control characters and Eight Ones character are non-standard because non-EBCDIC control characters appear in the range reserved for control characters, all common control characters are not present, and a non-EBCDIC control character replaces the Eight Ones character.
No special processing is performed by the database for control characters, except for Shift Out and Shift In, which switch to and from double-byte codepoints. The non-EBCDIC control characters Single Shift Two and Single Shift Three imply nothing about subsequent codepoints.