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Can a very large table be used for data retrieval?
Yes there may be some data designing concepts which does like “Divide and Rule” could be of help, but sticking to my scenario of a “Very Large Table” or may be “Very Large Data from which the filtering is to be done” , how it has to be handled if only using oracle database software. Hope my scenario is not a funny one. J and we said…
How many variables can be included in a data table?
Although it is limited to only one or two variables (one for the row input cell and one for the column input cell), a data table can include as many different variable values as you want. A scenario can have a maximum of 32 different values, but you can create as many scenarios as you want.
How to get data from a large table?
Full scan would rock and roll. If you say “no”, then I will tell you that this table has 100 blocks, and the first block has 100 rows with a value of 1, the second block has a 100 rows with 2 and so on. The query “where id = 1” should of course use an index to find the single block….
Why does it take so long to sort a table?
And if this is correct, then as the number of rows increases in the table the query is going to take more time, only because of the sorting operation. If it takes 3 seconds hours to find those 1,000,000 rows, then the 10 seconds to sort them is a large percentage of the execution time.
How to delete data from a large table in Oracle?
Vanilla delete: On a super-large table, a delete statement will required a dedicated rollback segment (UNDO log), and in some cases, the delete is so large that it must be written in PL/SQL with a COMMIT every million rows. Note that Oracle parallel DML allows you to parallelize large SQL deletes.
Which is the fastest way to delete data from a large table?
In cases where you are deleting more than 30-50% of the rows in a very large table it is faster to use CTAS to delete from a table than to do a vanilla delete and a reorganization of the table blocks and a rebuild of the constraints and indexes.