Create a release #3
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This is a critical piece for adoption. |
am357
added a commit
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this issue
Jul 26, 2024
```SQL
CREATE TABLE PETS (
id INT4,
breed STRING,
tag INT2
)
```
Tests:
```SQL
-- #1 should succeed
CAST(true AS INT2) --
-- #2 should fail
CAST((s : STRING) AS LIST)
-- #3 should succeed
CAST((i : INT2) AS INT4)
-- #4 should succeed
CAST((i : INT4) AS INT2)
```
#### Background context
As part of a specification work, we want to make the behavior for the #4 more visible:
From SQL-99 Section 6.22: <cast specification>:
```
If SD (source data type) is exact numeric or approximate numeric, then
Case:
i) If there is a representation of SV (source value) in the data type TD (target data type) that does not lose any leading si-gnificant digits after rounding or truncating if necessary, then TV is that representation.
The choice of whether to round or truncate is implementation-defined.
ii) Otherwise, an exception condition is raised: data exception — numeric value out of
range.
```
We can see this evaluation behavior in PostgresSQL v15:
Ref.: https://www.db-fiddle.com/f/vMY3Srd2bG6f3NshvTp3w1/0
```
-- succeeds
SELECT CAST((1::INT4) AS INT2);
-- fails: `Query Error: error: smallint out of range`
SELECT CAST((327686::INT4) AS INT2);
```
am357
added a commit
that referenced
this issue
Jul 29, 2024
Add more cast tests
```SQL
CREATE TABLE PETS (
id INT4,
breed STRING,
tag INT2
)
```
Tests:
```SQL
-- #1 should succeed
CAST(true AS INT2) --
-- #2 should fail
CAST((s : STRING) AS LIST)
-- #3 should succeed
CAST((i : INT2) AS INT4)
-- #4 should succeed
CAST((i : INT4) AS INT2)
```
#### Background context
As part of a specification work, we want to make the behavior for the #4 more visible:
From SQL-99 Section 6.22: <cast specification>:
```
If SD (source data type) is exact numeric or approximate numeric, then
Case:
i) If there is a representation of SV (source value) in the data type TD (target data type) that does not lose any leading si-gnificant digits after rounding or truncating if necessary, then TV is that representation.
The choice of whether to round or truncate is implementation-defined.
ii) Otherwise, an exception condition is raised: data exception — numeric value out of
range.
```
We can see this evaluation behavior in PostgresSQL v15:
Ref.: https://www.db-fiddle.com/f/vMY3Srd2bG6f3NshvTp3w1/0
```
-- succeeds
SELECT CAST((1::INT4) AS INT2);
-- fails: `Query Error: error: smallint out of range`
SELECT CAST((327686::INT4) AS INT2);
```
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The Getting Started instructions say:
In order to lower the bar for adoption, provide a release in the
Releasestab. This will allow users to get started with it much easily.The text was updated successfully, but these errors were encountered: