RE: [Firebird-devel] XML Load/Dump Utility

[Leyne, S. <Se...@br...>]

Leyne, Sean wrote:



	   <metadata>
	      <table name=3D"EMPLOYEE">
	         <column name=3D"SALARY" type=3D"double" scale=3D"-2"
	    nullable=3D"yes"/>

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This presentation is 'unexpected' (I didn't expect it).
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Although "double" is the true datatype, it is not the SQL datatype which
I expected to be used in the DDL (i.e. NUMERIC( 10, 2)).  Doesn't this
representation loose the accuracy of data schema?
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I haven't a clue what the original DDL looked like, but the database
created from the standard employee.fbk file has the employee salary
field defined with a double (aka long float) and a scale of -2.  I
report what I see.

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<SL> FYI, The original DDL was NUMERIC( 10, 2).

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<SL> Then what is the use of the schema information in the XML? =20

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<SL> By your own words, it doesn't provide true backup/restore
functionality; since it doesn't care about maintaining the original
schema definition (just a generalization of the datatypes).

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<SL> The JDBC conventions are more than appropriate for Java and (as you
suggest) internal uses, there are plenty of languages where a NUMERIC(
10, 2) and NUMERIC( 15, 2) would have significantly different meanings,
due to the data access components.  Therefore, the load/dump utility
could produce a database which is incompatible with the target
application.

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Remember my stock advice to fledgling language designers: Always pick
bad keywords so meddlers have something to change.

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<SL> Yes, I remember it well!  You've gotten me to bite that apple more
than once!!!.

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Sean