Slide 9.4: Meta data

Slide 9.3: SQL exceptions
Slide 9.5: A dynamic database access
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Meta Data

Metadata is information about a particular data set which may describe, for example, how, when, and by whom it was received, created, accessed, and/or modified and how it is formatted.

Result Set Meta Data
The java.sql.ResultSetMetaData interface provides extra information about ResultSet. The following information is provided by the interface:

How many columns are in the result set?
Are column names case-sensitive?
Can you search on a give column?
Is NULL a valid value for a given column?
How many characters is the maximum display size for a column?
What label should be used in a display header for the column?
What is the name of a given column?
What table did a give column come from?
What is the data type of a given column?

Database Meta Data
The java.sql.DatabaseMetaData interface provides methods that tell you about the database for a given Connection object, including:

What tables exist in the database?
What user name is being used by this connection?
Is this database connection read-only?
What keywords are used by the database that are not SQL2?
Does the database support column aliasing?
Are multiple result sets from an execute call supported?
Are outer joins supported?
What are the primary keys for a table?

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Slide 9.3: SQL exceptions
Slide 9.5: A dynamic database access
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“It is amazing how complete is the delusion that beauty is goodness.”
― Leo Tolstoy, The Kreutzer Sonata