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1878.5.4
by Brian Aker
Update documentation. |
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Updating Data
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1900.2.8
by Stewart Smith
fix docs warning: underline/overline too short for update.rst |
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1878.5.4
by Brian Aker
Update documentation. |
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In Dizzle you can make use of UPDATE to modify an existing record in a table. |
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A type query: |
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1994.5.4
by Stewart Smith
UPDATE has a condition |
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UPDATE TABLE_1 SET a="1" WHERE <condition>; |
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1878.5.4
by Brian Aker
Update documentation. |
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1994.4.38
by Marisa Plumb
multi-table exlanation to address https://bugs.launchpad.net/drizzle/+bug/686641 |
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Multi-table delete and multi-table update code was removed from Drizzle. |
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Multi-update/delete can be accomplished through subqueries. For example: ::
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UPDATE tableX SET tableXfield = (SELECT MAX(tableY.tableYfield) FROM tableY WHERE tableX.tableXfield = tableY.tableYfield)
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In other database frameworks, multi-update and multi-delete are used to change information in *one* table, but the rows to change are determined by using more than one table. In that case, subqueries work to address the issue of changing information in one table based on information in more than one table.
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