Seagate ST43401N/ND Informations techniques télécharger pdf (Page 143)

Migrating to Sybase Adaptive Server Enterprise 11.5 C-3

Adaptive Server Enterprise 11.5 Migration Approach Outline

Example:

update tableA set field1 =

(select max(field1) from tableB TB

where tableA.field = TB.field1)˙

• Identify subqueries using distinct/in/not/exists/any clauses.

Example 1:

select count(*) from publishers

where exists (select * from titles

where titles.pub_id = publishers.pub_id)

Example 2:

select pub_name from publishers

where pub_id in

(select distinct pub_id from titles

where titles.pub_id = publishers.pub_id)

PHASE 3: Issues Identiﬁed by Object Compilation in System 11

After upgrade, the following objects will be created in sequence:

tables, indexes, user stored procedures, triggers, views, users, and

permissions. We will then identify and address any issues found by

the SQL Server parser:

• Self-join format (repeated table names) must include table aliases.

• Identify NULL column headings in select into using aggregates

(

avg, min, max, sum, count)

• Deﬁned table aliases in queries must be used for column

references (also called correlation name handling)

PHASE 4: Manual Analysis and Resulting Changes to Object Code

After all objects have been successfully created on System 11, the

following issues need to be identiﬁed and documented by Sybase

staff. Testing and changes will be performed by Acme Financial staff

to ensure similar behavior between current and new objects:

• Identify objects with subqueries by using

sp_procqmode against

database

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Seagate ST43401N/ND Informations techniques Page 143