Details
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Bug
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Status: Closed (View Workflow)
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Minor
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Resolution: Duplicate
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None
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None
Description
MariaDb returns some nulls as collation info.
That crashes the .Net MySql driver and Oracle os not willing to fix their driver.
–
On connect, the driver tries to load collations IDs and cast them to
integers.
However collation is nullable and there are some null-collations, for
example:
+--------------------------------+----------+------+---------+----------+---------+
|
| Collation | Charset | Id | Default | Compiled
|
| Sortlen |
|
+--------------------------------+----------+------+---------+----------+---------+
|
|
|
| uca1400_ai_ci | NULL | NULL | NULL | Yes
|
| 8 |
|
| uca1400_ai_cs | NULL | NULL | NULL | Yes
|
| 8 |
|
| uca1400_as_ci | NULL | NULL | NULL | Yes
|
| 8 |
|
| uca1400_as_cs | NULL | NULL | NULL | Yes
|
| 8 |
|
So the driver fails to connect the database:
InvalidCast_FromDBNull: Object cannot be cast from DBNull to other
types.
Driver has the following code:
MySqlCommand mySqlCommand = new MySqlCommand("SHOW COLLATION", |
connection);
|
try |
{
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using MySqlDataReader mySqlDataReader = |
mySqlCommand.ExecuteReader();
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CharacterSets = new Dictionary<int, string>(); |
while (mySqlDataReader.Read()) |
{
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CharacterSets[Convert.ToInt32(mySqlDataReader["id"], |
NumberFormatInfo.InvariantInfo)] =
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mySqlDataReader.GetString(mySqlDataReader.GetOrdinal("charset")); |
}
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}
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catch (Exception ex) |
{
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MySqlTrace.LogError(ThreadID, ex.Message);
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throw; |
}
|
–
See e.g.: https://bugs.mysql.com/bug.php?id=109331
Attachments
Issue Links
- duplicates
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- Closed
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- is caused by
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MDEV-27009 Add UCA-14.0.0 collations
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- Closed
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Activity
danblack, I do not think we can force anyone to MySqlConnector no matter how good it is, the Oracle's connector remains slightly more popular.
It is not a drop-in, and people may depend on other open source or closed source software, which happened to use Oracle's connector
Also, as we promised client compatibity, I think we should try to keep this promise
I tried to collect some links on the internet for this issue , it is in MDEV-31608 . We broke OnlyOffice, PowerBI, Toad, and some other stuff with NULL collation ids (something that nobody uses, and something that could be put into a dedicated table).
Is there a reason the https://github.com/mysql-net/MySqlConnector and MariaDB Connector/J are unacceptable solutions?