Seagate ST43401N/ND Información técnica descargar pdf (Pagina 68)

5-14 Implement: Making Required Application Changes

If Your Current Version is 4.x Adaptive Server Enterprise 11.5

In version 4.x, SQL Server switched expr2 and expr3 automatically at

compile time if it knew that expr2 was greater than expr3. In other

words, it would process “250 between 400 and 200” as though it were

the same as “250 between 200 and 400”

As of version 10.0, SQL Server processes such inverted statements as

“false”.

Here is an example that compares releases:

create table demo (id int)

insert into demo values (250)

select id from demo

where id between 400 and 200

ANSI Comments

ANSI comments start with two or more consecutive hyphens

(-- ). They terminate in a new line. SQL Server adopted this

convention in 10.0. This may cause come current applications to

break if they contain syntax such as:

select 5--2

To avoid this problem, Rewrite these types of expressions with either

of the following:

• Parentheses

select 5 - (-2)

• Extra spaces

select 5 - -2

Correlation Names

ANSI requires correlation names on self-joins. The following query is

now invalid:

select columns from table1, table1

where clause ...

This query must be rewritten as:

Release 4.x

Results

Release 10.x and 11.x

Results

250 no rows returned

1 2 ... 63 64 65 66 67 68 69 70 71 72 73 ... 171 172

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Seagate ST43401N/ND Información técnica Pagina 68