Converting a nullable source to a non-nullable result

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abc123
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Post by abc123 »

Ray, I am just curious. When you say "metadata capture", aren't you talking about when Datastage compiler does the metadata capture during the outcome of the SQL?
ray.wurlod
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Post by ray.wurlod »

Not quite, I'm talking about when the running job queries the database server to verify the data types of each column, so that it can report data type mismatches. It's my understanding that, whenever a function or expression appears in the SQL, that the database server reports the column as nullable, since there is no metadata in the system tables to say that there is a NOT NULL constraint.
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sreddy
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Post by sreddy »

ABC123


After selecting the data, usually we are checking database connection; column definition of metadata is matching with base table. All these happened Oracle, ODBC, Sequential File stage except Hash File


As per my knowledge a copy of Table Definition (Meta Data) is holding in Stage level. When we compile it checks the mapping of job. When we are run the job then only it validates source definition with Target definition.

All the above information is as per my knowledge.....



abc123 wrote:Ray, I am just curious. When you say "metadata capture", aren't you talking about when Datastage compiler does the metadata capture during the outcome of the SQL?
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