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Table Sources
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For each table, you may specify a lock type for concurrency control. XLOCK ROW puts an exclusive lock on each row that is used in the query. XLOCK TABLE puts an exclusive lock on the whole table.
The table_sources specify the database tables, or sub-queries, or any joined combination of these to draw the data from. A JOIN can be used to select from multiple tables. Scimore supports the standard SQL join types:
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Join type |
Explanation |
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INNER (default) |
This will return a row for each combination of rows from the left and right tables: the Cartesian product. The ON clause is used to select only the matches desired. |
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LEFT [OUTER] |
Like the INNER join, this will return a row for each combination matching the left and right tables. Additionally, a row is returned for any row that does not satisfy the join ON condition in the left table, for which, values from the right table will be NULL. |
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RIGHT [OUTER] |
The same as the LEFT OUTER join, but with the left and right roles reversed. |