COPY

The COPY utility takes image copies - backups - of DB2 table spaces. These copies are what the RECOVER utility restores when data is lost or corrupted. Without regular COPY jobs, you have nothing to recover from.

What is COPY

• COPY writes the pages of a table space to sequential data sets called image copies.
• Each copy is registered in the SYSIBM.SYSCOPY catalog table with its timestamp and type.
• You can copy a full table space, a single partition, or a list of table spaces.
• COPYDDN names the DD statements in the JCL that receive the copy data sets.
• Always make two copies on different volumes when the data is critical.

Full vs incremental COPY

• FULL YES copies every page of the table space - a complete backup.
• FULL NO (incremental) copies only the pages changed since the last full or incremental copy.
• Incremental copies are faster and smaller, but RECOVER must apply the full copy plus all incrementals.
• Take a full copy regularly (for example weekly) and incrementals in between (for example daily).
• CHANGELIMIT can trigger a full copy automatically when enough pages have changed.

SHRLEVEL options

• SHRLEVEL REFERENCE is the default - applications can read but not update during the copy.
• SHRLEVEL CHANGE allows updates during the copy; DB2 logs the changes so the copy stays consistent.
• After a LOAD with LOG NO, the table space is in COPY pending status until you take a full COPY.
• COPYTOCOPY makes a backup copy of an existing image copy, for example to send one offsite.

Example of a COPY control statement:-