I can’t reproduce your issue with the following mysql script:
mysql> drop table if exists objects_de; create table objects_de(name text indexed attribute , maincatalog text indexed attribute, itempath text indexed attribute , manufacturer text indexed attribute , articlenumber text indexed attribute, expltext text indexed attribute , decltext text indexed attribute , itemid string , previewid string , sizex float , sizey float , sizez float , creation uint , classname string , contenthash string) regexp_filter='ß => ss' regexp_filter='ü => ue' regexp_filter='ä => ae' regexp_filter='ö => oe' regexp_filter='Ü => ue' regexp_filter = 'Ä => ae' regexp_filter = 'Ö => oe' morphology='lemmatize_de' exceptions='/tmp/exceptions' wordforms='/tmp/wordforms' index_exact_words='1'; insert into objects_de(name, maincatalog) values('Bank 4 + Polster','af9ec'), ('002_Sofa mit Kissen', '63e8e'); SELECT * FROM objects_de WHERE MATCH('"Polster"') AND REGEX(maincatalog, '5b901Dev|AndiDev|2a10859dffc5916631b2e27266f161ef|7d81a|fb3483aa57d7fbdcae0828472b683531|2304a|24992eb534cffcfe6bafdc57f6c1a49d|7dda5|6f404e8a0bb468dba3098ffa60f5acba|143799dbd2ddcbd8ae0f1934000bf248|45199|5146b|a36fa45bfbcb3a3eb4ea74bd60452977|36a7d59c2a26c3482e74d0d62d326e7f|babcc|fa1be21c4f80fb2f8b229dca2816d5f6|ac9f6|fc06eba748ec04e24dd5973430ad17a7|eb8d891367e87b9927ab7ec14a8af050|fbf7a|361d0|e3af4aac2d665ac76f8a3b210d91162d|644cc|83431128947fa530d8e172235240540d|3987d|14e61|675474351bb08ff01ba52802d4548173|71e3f|31202f76b785bc46b9daa6a5902e05a4|5533c|e9519|1932020bd014bc45d03c76b8c73ff025|af9ec|644ccit|644ccnl|644ccpl|644ccsk|83431128947fa530d8e17223524054fr|966a47d54e0b254dd9a9efd2fb69dec8|6f814|b15f5|85e709d8ccc78dc7859deda0cdd63d4d|aaaaa|aaaab|77611|ceda7cf57ecc60ea3d817da054820829|40872|e4271a55fd51b22ef2ac4df07c439f47|52b134cc0e4830328a572d871548d625|7bcbd|717ca8e1745ff6cfcc59fdd2346280df|9ddbf|a0e86|5b90f|5b90i|5b90nl|5b90pl|5b90sk|bbbfr|bbbit|bbbsk|5b911Dev|1277c358c1138b876fcec5cb48fa94a3|63e8e|cbaf460e7f3bc6fbe7f7ef849b34f4aa|e67f0|166f7|22679398192af1faea12c2c63491227b|6fc8ca7f089b356010eecbfd554be34e|d97e3|1984480425c4c11728f67128a9c74591|5b901|7d3cbb54f4f73cd9d83012fcb6bc0a6f|f3f8d|||1c38c6a4a160cc375db174aed1c60806|a0193|5fe4c|896c1|5ef3beca513d27fdb7f721d6384579d9|bd02a|testid|babcca|d3bfb|e29cd6f751e1ad79c42d976ab3ba41ff|4f334e9098b9ea62d7a59916ebd70f75|47765720b802402b7ee0010f9faa8d6d|d8cece5a11627b4b4ab1a4e2976e6578|bb5bc53cbb6a1e8d23b3aa262957dc7b|b3c7996ad575097c5abb426313406fa1|ec415|cb2a3|79951f669f6ffc2fc70e0005dfd06bab|1f83375cf673ed76c59007761e0a13ac|cf6f8|39e61|68de5bcb468538e0811fdd9d22230f4f') ORDER BY Name ASC LIMIT 0 , 60 OPTION field_weights=(name=10, maincatalog=1, itempath=3, manufacturer=9, articlenumber=9, classname=1, expltext=1, decltext=1), max_matches = 60\G show warnings;
--------------
drop table if exists objects_de
--------------
Query OK, 0 rows affected (0.00 sec)
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create table objects_de(name text indexed attribute , maincatalog text indexed attribute, itempath text indexed attribute , manufacturer text indexed attribute , articlenumber text indexed attribute, expltext text indexed attribute , decltext text indexed attribute , itemid string , previewid string , sizex float , sizey float , sizez float , creation uint , classname string , contenthash string) regexp_filter='ß => ss' regexp_filter='ü => ue' regexp_filter='ä => ae' regexp_filter='ö => oe' regexp_filter='Ü => ue' regexp_filter = 'Ä => ae' regexp_filter = 'Ö => oe' morphology='lemmatize_de' exceptions='/tmp/exceptions' wordforms='/tmp/wordforms' index_exact_words='1'
--------------
Query OK, 0 rows affected (0.01 sec)
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insert into objects_de(name, maincatalog) values('Bank 4 + Polster','af9ec'), ('002_Sofa mit Kissen', '63e8e')
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Query OK, 2 rows affected (0.00 sec)
--------------
SELECT * FROM objects_de WHERE MATCH('"Polster"') AND REGEX(maincatalog, '5b901Dev|AndiDev|2a10859dffc5916631b2e27266f161ef|7d81a|fb3483aa57d7fbdcae0828472b683531|2304a|24992eb534cffcfe6bafdc57f6c1a49d|7dda5|6f404e8a0bb468dba3098ffa60f5acba|143799dbd2ddcbd8ae0f1934000bf248|45199|5146b|a36fa45bfbcb3a3eb4ea74bd60452977|36a7d59c2a26c3482e74d0d62d326e7f|babcc|fa1be21c4f80fb2f8b229dca2816d5f6|ac9f6|fc06eba748ec04e24dd5973430ad17a7|eb8d891367e87b9927ab7ec14a8af050|fbf7a|361d0|e3af4aac2d665ac76f8a3b210d91162d|644cc|83431128947fa530d8e172235240540d|3987d|14e61|675474351bb08ff01ba52802d4548173|71e3f|31202f76b785bc46b9daa6a5902e05a4|5533c|e9519|1932020bd014bc45d03c76b8c73ff025|af9ec|644ccit|644ccnl|644ccpl|644ccsk|83431128947fa530d8e17223524054fr|966a47d54e0b254dd9a9efd2fb69dec8|6f814|b15f5|85e709d8ccc78dc7859deda0cdd63d4d|aaaaa|aaaab|77611|ceda7cf57ecc60ea3d817da054820829|40872|e4271a55fd51b22ef2ac4df07c439f47|52b134cc0e4830328a572d871548d625|7bcbd|717ca8e1745ff6cfcc59fdd2346280df|9ddbf|a0e86|5b90f|5b90i|5b90nl|5b90pl|5b90sk|bbbfr|bbbit|bbbsk|5b911Dev|1277c358c1138b876fcec5cb48fa94a3|63e8e|cbaf460e7f3bc6fbe7f7ef849b34f4aa|e67f0|166f7|22679398192af1faea12c2c63491227b|6fc8ca7f089b356010eecbfd554be34e|d97e3|1984480425c4c11728f67128a9c74591|5b901|7d3cbb54f4f73cd9d83012fcb6bc0a6f|f3f8d|||1c38c6a4a160cc375db174aed1c60806|a0193|5fe4c|896c1|5ef3beca513d27fdb7f721d6384579d9|bd02a|testid|babcca|d3bfb|e29cd6f751e1ad79c42d976ab3ba41ff|4f334e9098b9ea62d7a59916ebd70f75|47765720b802402b7ee0010f9faa8d6d|d8cece5a11627b4b4ab1a4e2976e6578|bb5bc53cbb6a1e8d23b3aa262957dc7b|b3c7996ad575097c5abb426313406fa1|ec415|cb2a3|79951f669f6ffc2fc70e0005dfd06bab|1f83375cf673ed76c59007761e0a13ac|cf6f8|39e61|68de5bcb468538e0811fdd9d22230f4f') ORDER BY Name ASC LIMIT 0 , 60 OPTION field_weights=(name=10, maincatalog=1, itempath=3, manufacturer=9, articlenumber=9, classname=1, expltext=1, decltext=1), max_matches = 60
--------------
*************************** 1. row ***************************
id: 1515200002673082374
creation: 0
sizex: 0.000000
sizey: 0.000000
sizez: 0.000000
name: 002_Sofa mit Kissen
maincatalog: 63e8e
itempath:
manufacturer:
articlenumber:
expltext:
decltext:
itemid:
previewid:
classname:
contenthash:
*************************** 2. row ***************************
id: 1515200002673082373
creation: 0
sizex: 0.000000
sizey: 0.000000
sizez: 0.000000
name: Bank 4 + Polster
maincatalog: af9ec
itempath:
manufacturer:
articlenumber:
expltext:
decltext:
itemid:
previewid:
classname:
contenthash:
2 rows in set, 1 warning (0.00 sec)
--------------
show warnings
--------------
+---------+------+-----------------------------------------------------------------------------------+
| Level | Code | Message |
+---------+------+-----------------------------------------------------------------------------------+
| warning | 1000 | index objects_de: Fields specified in field_weights option not found: [classname] |
+---------+------+-----------------------------------------------------------------------------------+
1 row in set (0.00 sec)
The external files are:
➜ ~ cat /tmp/exceptions
Polster => Kissen
➜ ~ cat /tmp/wordforms
Polster > Kissen
Please try to modify it making it closer to your situation until it starts reproducing and provide what you get.