I've about 200 tables in SQL Server 2005 database. Almost tables has column name "AAA" which I want to set FK to column A_ID in table tbl_AAA. I want to know, how can I do this in SQL Server 2005?
You can use the system view "INFORMATION_SCHEMA.COLUMNS" and build up a query which will result in the DDL statement required to carry out the task.
You can paste the output of this into SSMS and exceute it. I've done this of the top of my head so you may want to check/tweak/correct to suite your needs.