sql: fix ColumnAccessExpr.Eval with NULL inner expression #78423
Conversation
|
This change is |
There was a problem hiding this comment.
Good fix! Nice job reverse-engineering the test case.
Reviewable status:
complete! 1 of 0 LGTMs obtained (waiting on @cucaroach)
|
The test case from the first commit revealed another bug, #75101. I've added another commit to address it, so please take another look @msirek @cucaroach. |
Previously, `ColumnAccessExpr.Eval` would panic if the `ColumnAccessExpr`'s inner expression evaluated to `NULL`, because it attempted to cast this `NULL` to a `DTuple`. Now, if the inner expression is `NULL`, `ColumnAccessExpr.Eval` returns `NULL`. Fixes cockroachdb#78159 Release note (bug fix): A bug has been fixed that caused an internal error when the inner expression of a column access expression evaluated to `NULL`. For example, evaluation of the expression `(CASE WHEN b THEN ((ROW(1) AS a)) ELSE NULL END).a` would error when `b` is `false`. This bug has been present since version 19.1 or earlier.
…pleExprs
Previously, an expression that produced a tuple from several potential
values was typed as a tuple without any labels. This prevented a tuple's
column to be accessed by a label name.
For example, the expression below would result in the error "could not
identify column 'a' in record data type".
SELECT (CASE WHEN true THEN (ROW(1) AS a) ELSE (ROW(2) AS a) END).a
Now, the labels of the first tuple are used in the type of the outer
expression.
Fixes cockroachdb#78515
Release note (bug fix): A bug has been fixed that caused an error when
accessing a named column of a labelled tuple. The bug only occurred when
an expression could produce one of several different tuples. For
example, `(CASE WHEN true THEN (ROW(1) AS a) ELSE (ROW(2) AS a) END).a`
would fail to evaluate. This bug was present since version 22.1.0.
Although present in previous versions, it was impossible to encounter
due to limitations that prevented using tuples in this way.
mgartner
force-pushed
the
78159-column-access-fix
branch
from
a33dbb7
to
ae9a4c2
Compare
|
Friendly ping to take a look at the latest commit. @msirek @cucaroach Thanks! |
|
Friendly ping 😃 |
There was a problem hiding this comment.
The latest code revision looks good. I tried out some test cases and all cases enforce that all THEN and ELSE branches conform to the type of the first THEN branch.
Reviewable status:
|
TFTRs! bors r+ |
|
Build succeeded: |
|
I guess once its merged reviewable goes into retirement? Anyways |
sql: fix ColumnAccessExpr.Eval with NULL inner expression
Previously,
ColumnAccessExpr.Evalwould panic if theColumnAccessExpr's inner expression evaluated toNULL, because itattempted to cast this
NULLto aDTuple. Now, if the innerexpression is
NULL,ColumnAccessExpr.EvalreturnsNULL.Fixes #78159
Release note (bug fix): A bug has been fixed that caused an internal
error when the inner expression of a column access expression evaluated
to
NULL. For example, evaluation of the expression(CASE WHEN b THEN ((ROW(1) AS a)) ELSE NULL END).awould error whenbisfalse. This bug has been present since version 19.1 or earlier.sql: include tuple labels in types returned from typeCheckSameTypedTupleExprs
Previously, an expression that produced a tuple from several potential
values was typed as a tuple without any labels. This prevented a tuple's
column to be accessed by a label name.
For example, the expression below would result in the error "could not
identify column 'a' in record data type".
Now, the labels of the first tuple are used in the type of the outer
expression.
Fixes #78515
Release note (bug fix): A bug has been fixed that caused an error when
accessing a named column of a labelled tuple. The bug only occurred when
an expression could produce one of several different tuples. For
example,
(CASE WHEN true THEN (ROW(1) AS a) ELSE (ROW(2) AS a) END).awould fail to evaluate. This bug was present since version 22.1.0.
Although present in previous versions, it was impossible to encounter
due to limitations that prevented using tuples in this way.