How to select records using Index key in Firebird?

MS Compact SQL
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1. Table creation

CREATE TABLE ProductsWIndex(ProductID int IDENTITY(1,1), ProductName nvarchar(50))

2. Create Index

CREATE INDEX index_productID ON ProductsWIndex (ProductID)

3. Select records using Index key

SELECT * FROM ProductsWIndex WITH (INDEX(index_productID)) WHERE ProductID < @ProductID



So please help me....how to select records in faster way using the Index 'index_productID' in Firebird SQL?

Firbird will use the PK without your help.

At the purest level, SQL is a declarative language.
That means you 'declare' what you want and the SQL server implementation decides how to fulfill it.

Thanks for your reply.

I have one small doubt.

Here while table creation i didn't set ProductID as Primary key.

So while executing SELECT * FROM ProductsWIndex
WHERE ProductID < :ProductID refers index_productID index table??

Please tell me how indexing is working in the above query?

As long as the index exists it will be used provided the optimizer thinks it will be beneficial.

All SQL tables should have a PK defined. Either a natural PK or a surrogate one.

Thanks for your reply.

I tried with

SELECT * FROM ProductsWIndex WHERE ProductID < @ProductID PLAN (ProductsWIndex INDEX (index_productID))

Is the correct way of selecting records faster using Index key??

I give up.
Perhaps someone more articulate than I can explain better.

Thanks for your reply.