data types for calculated columns

[Larry Weng <weng@xxxxxxxxxxxxx>]

Hi,

Here is how to reproduce my problem.

1> create table t1(a bigint);

2> insert into t1(a) values(2);

3> create table t2(b double);

4> insert into t2(b) values(3);

5> select t1.a/t2.b as c from t1,t2;
+------------------+
| c                |
+------------------+
| 0.66666666666667 |
+------------------+

6> create table t3 select t1.a/t2.b as c from t1,t2;

7> select format(c,16) from t3;
+------------------+
| format(c,16)     |
+------------------+
| 0.70000000000000 |
+------------------+

Now you see 2/3 becomes 0.7. How can I keep the double precission here?

thanks
Larry Weng


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