Window specification [windowName] is not defined in the WINDOW clause.
WindowsSubstitution Logical Evaluation Rule
WindowsSubstitution
is a logical evaluation rule (i.e. Rule[LogicalPlan]
) that the logical query plan analyzer uses to resolve (aka substitute) WithWindowDefinition unary logical operators with UnresolvedWindowExpression to their corresponding WindowExpression with resolved WindowSpecDefinition.
WindowsSubstitution
is part of Substitution fixed-point batch of rules.
Note
|
It appears that WindowsSubstitution is exclusively used for pure SQL queries because WithWindowDefinition unary logical operator is created exclusively when AstBuilder parses window definitions.
|
If a window specification is not found, WindowsSubstitution
fails analysis with the following error:
Note
|
The analysis failure is unlikely to happen given AstBuilder builds a lookup table of all the named window specifications defined in a SQL text and reports a ParseException when a WindowSpecReference is not available earlier.
|
For every WithWindowDefinition
, WindowsSubstitution
takes the child
logical plan and transforms its UnresolvedWindowExpression expressions to be a WindowExpression with a window specification from the WINDOW
clause (see WithWindowDefinition Example).