Warning: BLOB/TEXT column 'referenceType' used in key specification without a key length

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: Master
• Fix Version/s: 7.2.10 DXP FP2, 7.2.10.1 DXP SP1, 7.2.X, 7.2.1 CE GA2, 7.3.10 DXP GA1, Master
• Component/s: DM > Upgrade
• Labels:
  • liferay-dxp-72-sp1
  • liferay-fixpack-dxp-2-7210
  • pt-upgrade-review
• Branch Version/s:
  7.2.x
• Backported to Branch:
  Committed
• Story Points: 1
• Fix Priority: 3
• Sprint: 032 - Nidoran
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/77265

Steps to reproduce:

1. Populate data from the attached database of 7.2.0 GA1.
2. Run upgrade client tool
3. Search for "WARN - BLOB/TEXT column 'referenceType'"

Expected results:
The upgrade is successful without warning.
Actual result:
The upgrade completes successfully but throws the following warning error.

[java] 2019-08-06 21:17:05.555 INFO  [main][BaseDB:109] create unique index IX_6B9E4A66 on DLOpenerFileEntryReference (referenceType, fileEntryId);
     [java] INFO - create unique index IX_6B9E4A66 on DLOpenerFileEntryReference (referenceType, fileEntryId);
     [java] 2019-08-06 21:17:05.556 WARN  [main][BaseDB:117] BLOB/TEXT column 'referenceType' used in key specification without a key length: create unique index IX_6B9E4A66 on DLOpenerFileEntryReference (referenceType, fileEntryId);
     [java] WARN - BLOB/TEXT column 'referenceType' used in key specification without a key length: create unique index IX_6B9E4A66 on DLOpenerFileEntryReference (referenceType, fileEntryId);