dbcli/sqlglot
1
0
Fork 0
Code Issues Activity

Adding upstream version 23.12.1.

Browse source 
Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 21:31:56 +01:00
parent efe1f986ea
commit 5d33af745d
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
93 changed files with 55455 additions and 52777 deletions
Download patch file Download diff file Expand all files Collapse all files

36
sqlglot/transforms.py
View file

@ -93,7 +93,9 @@ def eliminate_qualify(expression: exp.Expression) -> exp.Expression:
Some dialects don't support window functions in the WHERE clause, so we need to include them as
projections in the subquery, in order to refer to them in the outer filter using aliases. Also,
if a column is referenced in the QUALIFY clause but is not selected, we need to include it too,
otherwise we won't be able to refer to it in the outer query's WHERE clause.
otherwise we won't be able to refer to it in the outer query's WHERE clause. Finally, if a
newly aliased projection is referenced in the QUALIFY clause, it will be replaced by the
corresponding expression to avoid creating invalid column references.
"""
if isinstance(expression, exp.Select) and expression.args.get("qualify"):
taken = set(expression.named_selects)
@ -105,20 +107,31 @@ def eliminate_qualify(expression: exp.Expression) -> exp.Expression:
outer_selects = exp.select(*[select.alias_or_name for select in expression.selects])
qualify_filters = expression.args["qualify"].pop().this
expression_by_alias = {
select.alias: select.this
for select in expression.selects
if isinstance(select, exp.Alias)
}
select_candidates = exp.Window if expression.is_star else (exp.Window, exp.Column)
for expr in qualify_filters.find_all(select_candidates):
if isinstance(expr, exp.Window):
for select_candidate in qualify_filters.find_all(select_candidates):
if isinstance(select_candidate, exp.Window):
if expression_by_alias:
for column in select_candidate.find_all(exp.Column):
expr = expression_by_alias.get(column.name)
if expr:
column.replace(expr)
alias = find_new_name(expression.named_selects, "_w")
expression.select(exp.alias_(expr, alias), copy=False)
expression.select(exp.alias_(select_candidate, alias), copy=False)
column = exp.column(alias)
if isinstance(expr.parent, exp.Qualify):
if isinstance(select_candidate.parent, exp.Qualify):
qualify_filters = column
else:
expr.replace(column)
elif expr.name not in expression.named_selects:
expression.select(expr.copy(), copy=False)
select_candidate.replace(column)
elif select_candidate.name not in expression.named_selects:
expression.select(select_candidate.copy(), copy=False)
return outer_selects.from_(expression.subquery(alias="_t", copy=False), copy=False).where(
qualify_filters, copy=False
@ -336,13 +349,10 @@ def explode_to_unnest(index_offset: int = 0) -> t.Callable[[exp.Expression], exp
return _explode_to_unnest
PERCENTILES = (exp.PercentileCont, exp.PercentileDisc)
def add_within_group_for_percentiles(expression: exp.Expression) -> exp.Expression:
"""Transforms percentiles by adding a WITHIN GROUP clause to them."""
if (
isinstance(expression, PERCENTILES)
isinstance(expression, exp.PERCENTILES)
and not isinstance(expression.parent, exp.WithinGroup)
and expression.expression
):
@ -358,7 +368,7 @@ def remove_within_group_for_percentiles(expression: exp.Expression) -> exp.Expre
"""Transforms percentiles by getting rid of their corresponding WITHIN GROUP clause."""
if (
isinstance(expression, exp.WithinGroup)
and isinstance(expression.this, PERCENTILES)
and isinstance(expression.this, exp.PERCENTILES)
and isinstance(expression.expression, exp.Order)
):
quantile = expression.this.this