# Database Compare Schema finding false differences

**URL:** <https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914>\
**Category:** Toad for Oracle & DevOps Toolkit\
**Created:** [January 25, 2016, 6:32am UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914 "2016-01-25T06:32:13Z")\
**Posts on this page:** 13\
**Page:** 1

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**Author:** ![vincent\_86682](https://avatars.discourse-cdn.com/v4/letter/v/9de053/32.png) [@vincent\_86682](https://forums.toadworld.com/u/vincent_86682)\
**Post date:** [January 25, 2016, 6:32am UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/1 "2016-01-25T06:32:13Z")

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Hi,

I am using Toad 12.8 and the Database Compare Schema feature and its finding lots of false differences when comparing schema between an Oracle 12.1.0.2.0 and 11.2.0.3.0 database. In particular relating to:

- Table definition - “NO INMEMORY”.
- Comments - LOB storage specs (not really comments but table comments being parse wrong).
- Triggers - “description column of dba\_triggers” or “schema specification in description column of dba\_triggers” in “Differs By” but not differences when check.  
While none of these are show stoppers, it does cause quite a bit of pain as one have to check each of the differences to make sure that they are not “real” differences.

Am I doing something wrong hear? Is there a work around for this or is this a bug in Toad?

Vince

specification in description column of dba\_triggers

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**Author:** ![JohnDorlon](https://sea1.discourse-cdn.com/quest/user_avatar/forums.toadworld.com/johndorlon/32/9997_2.png) [@JohnDorlon](https://forums.toadworld.com/u/JohnDorlon)\
**Post date:** [January 25, 2016, 7:00am UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/2 "2016-01-25T07:00:03Z")

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Are you seeing a NO INMEMORY difference in the Results tab or only in the side-by-side viewer? I don’t see it in the results tab, and if you’re seeing it in the side-by-side viewer, that’s just because this param is in the script for Oracle 12.1.0.2 tables but not Oracle 11 tables. So some other difference is causing it to appear in the results tab, and the side-by-side viewer is not as smart and just showing text differences.

Can you be more specific about the lob storage and trigger differences? The only diff I’m seeing on LOBS is securefile vs basicfile and to me this seems like a legit difference. I don’t see the trigger problem.

A script to create some of these objects would be most helpful.

Thanks.

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**Author:** ![JohnDorlon](https://sea1.discourse-cdn.com/quest/user_avatar/forums.toadworld.com/johndorlon/32/9997_2.png) [@JohnDorlon](https://forums.toadworld.com/u/JohnDorlon)\
**Post date:** [January 25, 2016, 7:02am UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/3 "2016-01-25T07:02:30Z")

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Oh, and if you don’t care about LOB storage diffs, go to the “Storage Clause Options” tab within schema compare and uncheck “Lob Storage”.

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**Author:** ![vincent\_86682](https://avatars.discourse-cdn.com/v4/letter/v/9de053/32.png) [@vincent\_86682](https://forums.toadworld.com/u/vincent_86682)\
**Post date:** [January 25, 2016, 7:35am UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/4 "2016-01-25T07:35:06Z")

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Hi John,

Sorry, I should have been clearer, going to try and include some pics.

Now I am doing a "Connection" (live) based schema compare. I see these false differences in the "Results" tree. The only option checked on the "Storage Clause Options" is tablespace (the LOB option is unchecked).

Example: Differs by "comment" or "inmemory" (seems to be the same cause):

 ![CommentDiffDueToInMemory.jpeg](https://global.discourse-cdn.com/quest/original/2X/5/59dade1ce1caf8c56e60c0597f5d815c1dca69c1.jpeg)

Example: trigger diff example, no diff's shonw in visual compare.

 ![TriggerDiffs.jpeg](https://global.discourse-cdn.com/quest/original/2X/f/fd3709c3d200785616f695564d4ea5de650dec22.jpeg)

My Toad Options are:

 ![1104.Options.jpeg](https://global.discourse-cdn.com/quest/original/2X/a/a54743bfdb9ec8eea208273f21f5bf5e0aa0c7b5.jpeg)

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<div class="post-metadata">

**Author:** ![JohnDorlon](https://sea1.discourse-cdn.com/quest/user_avatar/forums.toadworld.com/johndorlon/32/9997_2.png) [@JohnDorlon](https://forums.toadworld.com/u/JohnDorlon)\
**Post date:** [January 25, 2016, 7:54am UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/5 "2016-01-25T07:54:27Z")

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“Schema specification in description column of dba\_triggers” means that one trigger was created like:

“create trigger schema.trigger\_name on table schema.table\_name…”

and the other was created like:

“create trigger trigger\_name on table table\_name…”

which isn’t terribly significant, unless you move your code from one schema to another. You can make that difference be ignored by going to the “object type specific options” tab and unchecking “compare schema name in description”. You don’t see these diffs in the side-by-side viewer because the “parse for schema names” option is also checked, which adds or remove the schema names according to the “include schema name in migration ddl” option (on the “misc options” tab).

As for tables, “no inmemory” will not make schema compare flag a difference unless both schemas are 12.1.0.2 or newer. However, if comparing 12.1.0.2 or newer with some older database, and there is some other difference that causes schema compare to flag a table, then you go to the side-by-side viewer, you’ll see “no inmemory” on the 12.1.0.2 script but not the older oracle version script. What does the “results” tab look like for the AGR table?

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**Author:** ![luishmr](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@luishmr](https://forums.toadworld.com/u/luishmr)\
**Post date:** [June 15, 2019, 10:40pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/6 "2019-06-15T22:40:18Z")

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and What about "description column of dba\_triggers" difference ?

Both sides has schema.trigger ...

 ![image](https://global.discourse-cdn.com/quest/original/2X/7/7e0c892a5b3bafbe73b0000fb39a73aaf040f8a9.png)

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**Author:** ![luishmr](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@luishmr](https://forums.toadworld.com/u/luishmr)\
**Post date:** [June 15, 2019, 10:42pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/7 "2019-06-15T22:42:11Z")

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I´m using TOAD for ORACLE 13.1.0.78

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**Author:** ![JohnDorlon](https://sea1.discourse-cdn.com/quest/user_avatar/forums.toadworld.com/johndorlon/32/9997_2.png) [@JohnDorlon](https://forums.toadworld.com/u/JohnDorlon)\
**Post date:** [June 16, 2019, 9:26pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/8 "2019-06-16T21:26:36Z")

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In both schemas/databases, run the query "select description from dba\_triggers where trigger\_name = 'TRG\_ALIVE\_DEL\_CONFIGURATION' (or any of your other triggers) to see what the exact difference is. It may or may not be significant. Please let me know what you find. If I need to make a change, or can make a more descriptive "differs by" comment, I will

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**Author:** ![luishmr](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@luishmr](https://forums.toadworld.com/u/luishmr)\
**Post date:** [June 16, 2019, 10:14pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/9 "2019-06-16T22:14:26Z")

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Thanks for your answer.

In one side we have upper case and other side has lower case. But the source code is the same in both sides.

 ![image](https://global.discourse-cdn.com/quest/original/2X/8/840723a8ea2df6f78ab35abe3b793f23c5be9a52.png)

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<div class="post-metadata">

**Author:** ![luishmr](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@luishmr](https://forums.toadworld.com/u/luishmr)\
**Post date:** [June 16, 2019, 10:15pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/10 "2019-06-16T22:15:09Z")

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![image](https://global.discourse-cdn.com/quest/original/2X/b/b5908aabcb1dc5b32fe7a13cef55d786a5c798bf.png)

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<div class="post-metadata">

**Author:** ![luishmr](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@luishmr](https://forums.toadworld.com/u/luishmr)\
**Post date:** [June 16, 2019, 10:16pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/11 "2019-06-16T22:16:07Z")

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but we ran the same script in both sides:

CREATE OR REPLACE TRIGGER LH\_ALIVE.TRG\_ALIVE\_DEL\_CONFIGURATION  
BEFORE DELETE  
ON lh\_alive.alive\_en\_configuration  
REFERENCING NEW AS new OLD AS old  
FOR EACH ROW  
WHEN (old.cd\_alive\_configuration = 1)  
BEGIN  
raise\_application\_error (-20999, 'Cannot delete CONFIGURATION #1.');  
END;  
/

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<div class="post-metadata">

**Author:** ![JohnDorlon](https://sea1.discourse-cdn.com/quest/user_avatar/forums.toadworld.com/johndorlon/32/9997_2.png) [@JohnDorlon](https://forums.toadworld.com/u/JohnDorlon)\
**Post date:** [June 17, 2019, 1:11pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/12 "2019-06-17T13:11:01Z")

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> but we ran the same script in both sides:

I don't know why Oracle would change the case. you can use these options to ignore minor differences like case, whitespace, etc.

![image](https://global.discourse-cdn.com/quest/original/2X/c/c071fe925dd1ff2c4cc85ed965182a18ba41edf4.jpeg)

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<div class="post-metadata">

**Author:** ![luishmr](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@luishmr](https://forums.toadworld.com/u/luishmr)\
**Post date:** [June 17, 2019, 3:21pm UTC](https://forums.toadworld.com/t/database-compare-schema-finding-false-differences/34914/13 "2019-06-17T15:21:52Z")

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Thank you very much John.

Luis H\>  
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