Connection level bulk copy metadata caching

[tkyc]

• Added connection level cache for destination column metadata.
• Added cacheBulkCopyMetadata boolean connection property.
  • true: driver will cache the metadata at the connection level
  • false: driver will not do any connection level metadata caching

Caveat: If the table changes in any way (column definition, new columns, deleted columns, etc..), then during a bulk copy the operation may or may not error out when caching is enabled. Just a note that there could be unintended consequences without warning.

[Jeffery-Wasty]

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