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We would put the TableColumn info of the TableSchema into the CatalogTable properties which would be used to persist. For every column expression, there are three items to persist:

• The column name
• The column data type
• The column expression of SQL-style string that looks like that how user writes them

When deserializing, we We use SqlParser to parse the expression strings to SqlNodeinto SqlNode, then converts it to RexNode and apply the projections.

Compatibility, Deprecation, and Migration Plan

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