sql - How to create index for dynamic search strings -

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I have little DB for academic purpose, and I have object tables. I have a unit-relation model in Power Designer ERM) and the program creates an index for serial ID for each table by default.

  1. I want to know how I use a query on an index like that. Then I want to find a product with my ID, but it is using index.
  2. Is it possible to do this choose a value from the supplier, where the name '% search%' like the name s.name by to do a search like a search ? I know that it is possible to create an index for the name, but for a search like I do not know how things work.

Let me know that I know when Oracle is useful, or if it is worth using index in a query, but at least, try to use index in my BD project May

1. By defining the column as the primary key (which is most likely to be your ID column), Oracle has made an indicator for this column. When you have a selection with WHERE id = 123 , then it will most likely to use that index. You can provide the Oracle in your query to use the index (in most cases), but this should not be necessary for you.

2. Oracle is not likely to use an index for LIKE (unless you do not know that your text starts with the detected string and you can use 'xyz%' Are). For more information about when and how to use an index for a complete table scan, see.

This article should provide information about how to handle full text searches.


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