Does out of line LOB storage of wide base table columns improve performance?
Yes. Typically, a SELECT statement selects more than one column from your base table. Because Oracle Text fetches columns to memory, it is more efficient to store wide base table columns such as LOBs out of line, especially when these columns are rarely updated but frequently selected. When LOBs are stored out of line, only the LOB locators need to be fetched to memory during querying. Out of line storage reduces the effective size of the base table making it easier for Oracle Text to cache the entire table to memory. This reduces the cost of selecting columns from the base table, and hence speeds up text queries. In addition, having smaller base tables cached in memory enables more index table data to be cached during querying, which improves performance.
Yes. Typically, a SELECT statement selects more than one column from your base table. Since Oracle Text fetches columns to memory, it is more efficient to store wide base table columns such as LOBs out of line, especially when these columns are rarely updated but frequently selected. When LOBs are stored out of line, only the LOB locators need to be fetched to memory during querying. Out of line storage reduces the effective size of the base table making it easier for Oracle Text to cache the entire table to memory. This reduces the cost of selecting columns from the base table, and hence speeds up text queries. In addition, having smaller base tables cached in memory enables more index table data to be cached during querying, which improves performance.
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