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Hi...

I am currently applying 8.11.1172 to my project. (EF core 2.1.1)
It is applied to the actual product, so it is urgent to correct it. :(

But, if I call Skip () after OrderBy (), an error occurs.

Here is sample
==============================================
List< AnalysisRequest> test = await m_dbContext.AnalysisRequests.AsNoTracking()
.OrderBy(i => i.RegDate)
.Skip(1)
.ToListAsync();

Here is query generated by ef
==============================================
SELECT t.*
FROM (
SELECT t0.*
FROM (
SELECT i.REQUEST_ID, i.DEVICE_ID, i.REG_DATE, i.REG_ID, i.REG_NAME, i.SEARCH_END, i.SEARCH_START, i.STATUS, i.VIRTUAL_DEVICE_ID, i.REG_DATE AS REG_DATE0, i.REG_DATE AS REG_DATE00
FROM ANALYSIS_REQUESTS i
ORDER BY c
LIMIT 2147483647 OFFSET :p__p_0
) AS t0
ORDER BY t0.REG_DATE00
LIMIT 2147483647 OFFSET :p__p_0
) AS t
ORDER BY t.REG_DATE0
LIMIT :p__p_1 OFFSET :p__p_0

Here is stack traces..
==============================================

Microsoft.EntityFrameworkCore.Database.Command: [2018-06-25 13:39:49][ERROR][Microsoft.EntityFrameworkCore.Database.Command] - Failed executing DbCommand (4ms) [Parameters=[p__p_0='?' (DbType = Int32)], CommandType='Text', CommandTimeout='30']
SELECT t.*
FROM (
SELECT t0.*
FROM (
SELECT i.REQUEST_ID, i.DEVICE_ID, i.REG_DATE, i.REG_ID, i.REG_NAME, i.SEARCH_END, i.SEARCH_START, i.STATUS, i.VIRTUAL_DEVICE_ID, i.REG_DATE AS REG_DATE0, i.REG_DATE AS REG_DATE00
FROM ANALYSIS_REQUESTS i
ORDER BY c
LIMIT 2147483647 OFFSET :p__p_0
) AS t0
ORDER BY t0.REG_DATE00
LIMIT 2147483647 OFFSET :p__p_0
) AS t
ORDER BY t.REG_DATE0
LIMIT 2147483647 OFFSET :p__p_0
예외 발생: 'Devart.Data.MySql.MySqlException'(System.Private.CoreLib.dll)
NNException: [2018-06-25 13:39:58][ERROR][NNException] - Unknown column 'c' in 'order clause'

One more thing I worry about.

Looking at the query generated above ...

It seems that there is no need for an internal query.

1. no need internal query #1...I think

SELECT i.REQUEST_ID, i.DEVICE_ID, i.REG_DATE, i.REG_ID, i.REG_NAME, i.SEARCH_END, i.SEARCH_START, i.STATUS, i.VIRTUAL_DEVICE_ID, i.REG_DATE AS REG_DATE0, i.REG_DATE AS REG_DATE00
FROM ANALYSIS_REQUESTS i
ORDER BY c
LIMIT 2147483647 OFFSET :p__p_0

2. no need internal query #2...I think

SELECT t0.*
FROM (
SELECT i.REQUEST_ID, i.DEVICE_ID, i.REG_DATE, i.REG_ID, i.REG_NAME, i.SEARCH_END, i.SEARCH_START, i.STATUS, i.VIRTUAL_DEVICE_ID, i.REG_DATE AS REG_DATE0, i.REG_DATE AS REG_DATE00
FROM ANALYSIS_REQUESTS i
ORDER BY c
LIMIT 2147483647 OFFSET :p__p_0
) AS t0
ORDER BY t0.REG_DATE00
LIMIT 2147483647 OFFSET :p__p_0




In addition, from the inner query to the order by command, it seems to affect performance.

Is this a performance issue?

Is there anyone here?

Please let me know when I can receive updates.
Depending on the answer, I can decide whether to wait for an update or roll back the source.

Thank you for your report. We have reproduced the issue and are investigating it. We will notify you about the result.

The bug with paging in EF Core 2.1 is fixed. The internal build with the fix: https://www.devart.com/pub/nuget_mysql_8_11_1186.zip.

dotConnect for MySQL 8.12 is released: viewtopic.php?f=2&t=37477.