#15320: MySQL Alter Table leaves Scale in Table properties for Real Datatype

tariqrahiman reported 2017-06-16T17:07:16Z · last modified 2017-06-30T01:38:21Z

MySQL Alter Table leaves Scale in Table properties for Real Datatype

Dev	tomconrad
QA	tariqrahiman

Priority	Low
Complexity	Unknown

Component	DB - MySQL
Version	18.0

Version: 18.0.14-6

Build #: 54743

Build Date: 2017-Jun-15 05:38:59 PM

Operating Environment: Mac OS X (10.12.3, x86_64) / UTF-8 / en / AU / Oracle Corporation 1.8.0_40-b27

Memory: Max=3,819,962,368; Total=1,399,848,960; Free=1,049,270,760; CPUs=8

MySQL Alter Table leaves Scale in Table properties for Real Datatype

Create a new MySQL Table and enter a table name

Add column c1 DECIMAL datatype and precision = 10, scale = 2

Now, change the datatype to REAL

hit Tab or use the mouse to move to a different column

You can see that the Scale remains and is not cleared.

Expected Result: When a decimal or Float datatype is changed to Real, the Scale needs to be cleared, the same way as precision

2 attachments

Screen Shot 2017-06-16 at 10.06.31 am.png

2017-06-16T17:07:16Z

73 KB
issue_15320.png

2017-06-28T12:50:54Z

63 KB

All Comments (5) Change History

tomconrad 2017-06-16T20:42:22Z

svn #54753 - Set the default values for precision and scale for the real, float and double datatypes.

Hi Tariq,

I just set the default values for those datatypes. Give it a try. If it works good, let me know because we should retrofit this to v18.

Thanks, Tom

dutondeumesh 2017-06-27T09:55:57Z · (edited)

Hi Tom,

Verified in ADS 19.0.0-alpha-61.

Verified default set values for below data types on different MySQL versions(5.1,5.5,5.7).

Decimal(10,0)

Double(16,4)

float(10,2)

Numeric(10,2)

Real(10,2)

Doubt clarification:

REAL is a synonym for DOUBLE, but default value set is different for both data types.

Is this expected behaviour?

tomconrad 2017-06-27T15:22:39Z · (edited)

Hi Umesh,

Thanks for testing... Real is usually synonymous with float type. That is why I made the precision and scale the same as a float. In the case of MySQL, it can be either double or float depending on how MySQL is configured. From the documentation...

MySQL treats DOUBLE as a synonym for DOUBLE PRECISION (a nonstandard extension). MySQL also treats REAL as a synonym for DOUBLE PRECISION (a nonstandard variation), unless the REAL_AS_FLOAT SQL mode is enabled.

That said, Since the default is double, I will change the precision and scale for real to be the same as double.

V19 - svn #54902. V18 - svn #54903

Tom

ashwini.chavan 2017-06-28T12:51:06Z

Verified Build: ADS 19.0.0-alpha-63. MySQL versions: 5.1, 5.4, 5.5, 5.6, 5.7

Default values displayed in CREATE TABLE UI as follows:(mentioned in round bracket)

Decimal(10,0)

Double(16,4)

float(10,2)

Numeric(10,0)

Real(16,4)(issue_15320.png)

tariqrahiman 2017-06-30T01:38:21Z

Verified in ADS v18.0.17-2

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MySQL Alter Table leaves Scale in Table properties for Real Datatype

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Issue #15320

Completion

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Aqua Data Studio / nhilam

Title

MySQL Alter Table leaves Scale in Table properties for Real Datatype

2 attachments

Issue #15320

Completion