Dataset group masking rules
A dataset group mask is a character string that describes the dataset group names for which you want information returned. Asterisks (*) and percent signs (%) are used to represent qualifiers or parts of qualifiers.
The information in the table explains the use of asterisks and percent signs in
masks.
| Mask characters | Description |
|---|---|
| * | A single asterisk by itself indicates that either a qualifier or one or more characters within a qualifier can occupy that position. An asterisk can precede or follow a set of characters. |
| ** | A double asterisk indicates that zero or more qualifiers can occupy that position. A double asterisk cannot precede or follow any characters; it must be preceded or followed by either a period or a blank. |
| % | A single percent sign by itself indicates that exactly one alphanumeric or national character can occupy that position. |
| %% | One to eight percent signs can be specified in each qualifier. |
Mask scenarios
Consider a scenario in which you have the following dataset groups:
- MYGROUP.DATA.SET1
- MYGROUP.DATA.SET2
- MYGROUP.DATA.SET30
- VSAM.MYGROUP.DATA.SET
Table 307 shows several masks and the information that each mask returns.
| Mask | Information returned | Information excluded |
|---|---|---|
| MYGROUP.DATA.* |
MYGROUP.DATA.SET1 MYGROUP.DATA.SET2 MYGROUP.DATA.SET30 |
VSAM.MYGROUP.DATA.SET |
| **.DATA.** |
MYGROUP.DATA.SET1, MYGROUP.DATA.SET2 MYGROUP.DATA.SET30, and VSAM.MYGROUP.DATA.SET |
- |
| MYGROUP.DATA.SET% |
MYGROUP.DATA.SET1 and MYGROUP.DATA.SET2 |
MYGROUP.DATA.SET30 and VSAM.MYGROUP.DATA.SET |
| MYGROUP.DATA.SET%% | MYGROUP.DATA.SET30 |
MYGROUP.DATA.SET1, MYGROUP.DATA.SET2, and VSAM.MYGROUP.DATA.SET |