Archives of the TeradataForum
Message Posted: Tue, 01 Apr 2008 @ 23:24:59 GMT
Subj: | | Re: Looping SQL Script in Queryman |
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From: | | McCall, Glenn David |
| But I'm a little curious about what SQL Statement gets repeated if you do the import function? | |
The one (and only) query gets repeated for each row in your import file.
I've only ever tried a single query during an import, but it would be an interesting experiment to try > 1.
Basically the fields in the import file are "mapped" into the locations identified by question marks and I'm guessing the whole query is
submitted for processing.
I believe SQLA uses prepared statements. This essentially means that the Teradata recognises a query that takes some number of values. These
values are to be supplied separately and at a later time. Then SQLA reads your import files and supplies those values 1 row at a time. In this
model, the query is only sent to TD once, parsing etc only occurs once and data values simply "flow into the system".
Glenn Mc
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