[SOLVED] Embarcadero InterBase 2020 Server Edition Update 6 views with more than 2 UNION ALL Select Statements Fails

Embarcadero InterBase 2020 Server Edition Update 6 views with more than 2 UNION ALL Select Statements Fails

I downloaded the latest Interbase from here https://altd.embarcadero.com/download/interbase/2020/latest/InterBase_2020_Windows.zip and used the trial version.

Upon installation, either as 32-bit or as 64-bit, and creating a database with all the default settings, I cannot run a view with more than two Union All Select statements. It gives the error: arithmetic exception, numeric overflow, or string truncation.

Here is the minimum reproducible error:

Install Interbase 2020 (any version of Interbase 2020, including the latest update 6 as of the time of asking this, gives the same error).
Create a new database with the default parameters (I tried also altering the default database creation parameters but it made no difference).
Create this table:

CREATE TABLE TESTTABLE1
(
     AUTO1 integer NOT NULL
    ,NAME1 varchar(100)
    ,CONSTRAINT PK_TESTTABLE1_0 PRIMARY KEY (AUTO1)
);

Insert one entry into this table:

INSERT INTO TESTTABLE1 (AUTO1, NAME1) VALUES (1, 'STUDENT1');

Create a view with more than one Union All statement:

CREATE VIEW VIEW2 (AUTO1, CUST1) AS  
    SELECT
         T1.AUTO1
        ,T1.NAME1
    FROM TESTTABLE1 T1

    UNION ALL

    SELECT
         T2.AUTO1
        ,T2.NAME1
    FROM TESTTABLE1 T2

    UNION ALL

    SELECT
         T3.AUTO1
        ,T3.NAME1
    FROM TESTTABLE1 T3;

Select from this view:

SELECT * FROM VIEW2;

Error: Error at line 1: arithmetic exception, numeric overflow, or string truncation

I noticed that when I have only one UNION ALL SELECT statement, it works correctly.

I also noted that when you show System Data(tables) and access the Data tab of the table RDB$VIEW_RELATIONS, in the view with two UNION ALL statements, it has only one entry, inserting only the last table from the select list. In the view that works, it has two tables.

Question: Is there a workaround?

Solution