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From Column order in Index on Ask Tom:

So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all).

Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

Ask Tom:

So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all).

Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

From Column order in Index on Ask Tom:

So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all).

Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

2 deleted 14 characters in body
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Ask Tom: "So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all)." Agree

So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all).

Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

Thanks, Andjelko Miovcic

Ask Tom: "So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all)." Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

Thanks, Andjelko Miovcic

Ask Tom:

So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all).

Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

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Ask Tom: "So, the order of columns in your index depends on HOW YOUR QUERIES are written. You want to be able to use the index for as many queries as you can (so as to cut down on the over all number of indexes you have) -- that will drive the order of the columns. Nothing else (selectivity of a or b does not count at all)." Agree, that we have to order columns based on where clause, but the statement "(selectivity of a or b does not count at all)" is not correct.)". The most selective columns should be leading if it is satisfied first role ("where clause")

Thanks, Andjelko Miovcic