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Merging upstream version 11.7.1.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 15:52:09 +01:00
parent 0c053462ae
commit 8d96084fad
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
144 changed files with 44104 additions and 39367 deletions
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135
sqlglot/transforms.py
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@ -103,7 +103,11 @@ def eliminate_qualify(expression: exp.Expression) -> exp.Expression:
if isinstance(expr, exp.Window):
alias = find_new_name(expression.named_selects, "_w")
expression.select(exp.alias_(expr.copy(), alias), copy=False)
expr.replace(exp.column(alias))
column = exp.column(alias)
if isinstance(expr.parent, exp.Qualify):
qualify_filters = column
else:
expr.replace(column)
elif expr.name not in expression.named_selects:
expression.select(expr.copy(), copy=False)
@ -133,9 +137,111 @@ def remove_precision_parameterized_types(expression: exp.Expression) -> exp.Expr
)
def unnest_to_explode(expression: exp.Expression) -> exp.Expression:
"""Convert cross join unnest into lateral view explode (used in presto -> hive)."""
if isinstance(expression, exp.Select):
for join in expression.args.get("joins") or []:
unnest = join.this
if isinstance(unnest, exp.Unnest):
alias = unnest.args.get("alias")
udtf = exp.Posexplode if unnest.args.get("ordinality") else exp.Explode
expression.args["joins"].remove(join)
for e, column in zip(unnest.expressions, alias.columns if alias else []):
expression.append(
"laterals",
exp.Lateral(
this=udtf(this=e),
view=True,
alias=exp.TableAlias(this=alias.this, columns=[column]), # type: ignore
),
)
return expression
def explode_to_unnest(expression: exp.Expression) -> exp.Expression:
"""Convert explode/posexplode into unnest (used in hive -> presto)."""
if isinstance(expression, exp.Select):
from sqlglot.optimizer.scope import build_scope
taken_select_names = set(expression.named_selects)
taken_source_names = set(build_scope(expression).selected_sources)
for select in expression.selects:
to_replace = select
pos_alias = ""
explode_alias = ""
if isinstance(select, exp.Alias):
explode_alias = select.alias
select = select.this
elif isinstance(select, exp.Aliases):
pos_alias = select.aliases[0].name
explode_alias = select.aliases[1].name
select = select.this
if isinstance(select, (exp.Explode, exp.Posexplode)):
is_posexplode = isinstance(select, exp.Posexplode)
explode_arg = select.this
unnest = exp.Unnest(expressions=[explode_arg.copy()], ordinality=is_posexplode)
# This ensures that we won't use [POS]EXPLODE's argument as a new selection
if isinstance(explode_arg, exp.Column):
taken_select_names.add(explode_arg.output_name)
unnest_source_alias = find_new_name(taken_source_names, "_u")
taken_source_names.add(unnest_source_alias)
if not explode_alias:
explode_alias = find_new_name(taken_select_names, "col")
taken_select_names.add(explode_alias)
if is_posexplode:
pos_alias = find_new_name(taken_select_names, "pos")
taken_select_names.add(pos_alias)
if is_posexplode:
column_names = [explode_alias, pos_alias]
to_replace.pop()
expression.select(pos_alias, explode_alias, copy=False)
else:
column_names = [explode_alias]
to_replace.replace(exp.column(explode_alias))
unnest = exp.alias_(unnest, unnest_source_alias, table=column_names)
if not expression.args.get("from"):
expression.from_(unnest, copy=False)
else:
expression.join(unnest, join_type="CROSS", copy=False)
return expression
def remove_target_from_merge(expression: exp.Expression) -> exp.Expression:
"""Remove table refs from columns in when statements."""
if isinstance(expression, exp.Merge):
alias = expression.this.args.get("alias")
targets = {expression.this.this}
if alias:
targets.add(alias.this)
for when in expression.expressions:
when.transform(
lambda node: exp.column(node.name)
if isinstance(node, exp.Column) and node.args.get("table") in targets
else node,
copy=False,
)
return expression
def preprocess(
transforms: t.List[t.Callable[[exp.Expression], exp.Expression]],
to_sql: t.Callable[[Generator, exp.Expression], str],
) -> t.Callable[[Generator, exp.Expression], str]:
"""
Creates a new transform by chaining a sequence of transformations and converts the resulting
@ -143,36 +249,23 @@ def preprocess(
Args:
transforms: sequence of transform functions. These will be called in order.
to_sql: final transform that converts the resulting expression to a SQL string.
Returns:
Function that can be used as a generator transform.
"""
def _to_sql(self, expression):
def _to_sql(self, expression: exp.Expression) -> str:
expression = transforms[0](expression.copy())
for t in transforms[1:]:
expression = t(expression)
return to_sql(self, expression)
return getattr(self, expression.key + "_sql")(expression)
return _to_sql
def delegate(attr: str) -> t.Callable:
"""
Create a new method that delegates to `attr`. This is useful for creating `Generator.TRANSFORMS`
functions that delegate to existing generator methods.
"""
def _transform(self, *args, **kwargs):
return getattr(self, attr)(*args, **kwargs)
return _transform
UNALIAS_GROUP = {exp.Group: preprocess([unalias_group], delegate("group_sql"))}
ELIMINATE_DISTINCT_ON = {exp.Select: preprocess([eliminate_distinct_on], delegate("select_sql"))}
ELIMINATE_QUALIFY = {exp.Select: preprocess([eliminate_qualify], delegate("select_sql"))}
UNALIAS_GROUP = {exp.Group: preprocess([unalias_group])}
ELIMINATE_DISTINCT_ON = {exp.Select: preprocess([eliminate_distinct_on])}
ELIMINATE_QUALIFY = {exp.Select: preprocess([eliminate_qualify])}
REMOVE_PRECISION_PARAMETERIZED_TYPES = {
exp.Cast: preprocess([remove_precision_parameterized_types], delegate("cast_sql"))
exp.Cast: preprocess([remove_precision_parameterized_types])
}