# Instance db siemens

**URL:** <https://forum.inductiveautomation.com/t/instance-db-siemens/40699>\
**Category:** Ignition\
**Tags:** ignition80\
**Created:** [November 16, 2020, 5:54pm UTC](https://forum.inductiveautomation.com/t/instance-db-siemens/40699 "2020-11-16T17:54:46Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![rcepeda](https://avatars.discourse-cdn.com/v4/letter/r/6a8cbe/32.png) [@rcepeda](https://forum.inductiveautomation.com/u/rcepeda)\
**Post date:** [November 16, 2020, 5:54pm UTC](https://forum.inductiveautomation.com/t/instance-db-siemens/40699/1 "2020-11-16T17:54:46Z")

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Hi,

I’m doing a migration from WINCC to Ignition, so there are some tags in a DB wich is a instance DB of a FB, so it isn´t a GLOBAL DB. There is any way to acces this instance DB from Ignition?  
I’m working with Ignition V8.0.12

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<div class="post-metadata">

**Author:** ![Kfoldesi](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kfoldesi/32/11327_2.png) [@Kfoldesi](https://forum.inductiveautomation.com/u/Kfoldesi)\
**Post date:** [November 17, 2020, 1:17pm UTC](https://forum.inductiveautomation.com/t/instance-db-siemens/40699/2 "2020-11-17T13:17:52Z")

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Each instance DB has it’s own number/name. Ignition doesn’t care if it is a global or instance DB. There may or may not be multiple instances. But, each instance DB will have the same tags.

PS  
if you are accessing the DB via number you have to use the number nomenclature: DBx.DBax where a is a letter indicating: none = bit, b = byte, w=word, d=double

if you are accessing the DB via “optimized access”, then use “DBName”.TagName. You can access a “Slice” of the tag by adding .%ax same letter description, x is a number starting with 0