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sqlglot.optimizer.normalize_identifiers

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 1from __future__ import annotations
 2
 3import typing as t
 4
 5from sqlglot import exp
 6from sqlglot._typing import E
 7from sqlglot.dialects.dialect import Dialect, DialectType
 8
 9
10@t.overload
11def normalize_identifiers(expression: E, dialect: DialectType = None) -> E:
12    ...
13
14
15@t.overload
16def normalize_identifiers(expression: str, dialect: DialectType = None) -> exp.Expression:
17    ...
18
19
20def normalize_identifiers(expression, dialect=None):
21    """
22    Normalize all unquoted identifiers to either lower or upper case, depending
23    on the dialect. This essentially makes those identifiers case-insensitive.
24
25    Note:
26        Some dialects (e.g. BigQuery) treat identifiers as case-insensitive even
27        when they're quoted, so in these cases all identifiers are normalized.
28
29    Example:
30        >>> import sqlglot
31        >>> expression = sqlglot.parse_one('SELECT Bar.A AS A FROM "Foo".Bar')
32        >>> normalize_identifiers(expression).sql()
33        'SELECT bar.a AS a FROM "Foo".bar'
34        >>> normalize_identifiers("foo", dialect="snowflake").sql(dialect="snowflake")
35        'FOO'
36
37    Args:
38        expression: The expression to transform.
39        dialect: The dialect to use in order to decide how to normalize identifiers.
40
41    Returns:
42        The transformed expression.
43    """
44    if isinstance(expression, str):
45        expression = exp.to_identifier(expression)
46    return expression.transform(Dialect.get_or_raise(dialect).normalize_identifier, copy=False)

def normalize_identifiers(expression, dialect=None): View Source

21def normalize_identifiers(expression, dialect=None):
22    """
23    Normalize all unquoted identifiers to either lower or upper case, depending
24    on the dialect. This essentially makes those identifiers case-insensitive.
25
26    Note:
27        Some dialects (e.g. BigQuery) treat identifiers as case-insensitive even
28        when they're quoted, so in these cases all identifiers are normalized.
29
30    Example:
31        >>> import sqlglot
32        >>> expression = sqlglot.parse_one('SELECT Bar.A AS A FROM "Foo".Bar')
33        >>> normalize_identifiers(expression).sql()
34        'SELECT bar.a AS a FROM "Foo".bar'
35        >>> normalize_identifiers("foo", dialect="snowflake").sql(dialect="snowflake")
36        'FOO'
37
38    Args:
39        expression: The expression to transform.
40        dialect: The dialect to use in order to decide how to normalize identifiers.
41
42    Returns:
43        The transformed expression.
44    """
45    if isinstance(expression, str):
46        expression = exp.to_identifier(expression)
47    return expression.transform(Dialect.get_or_raise(dialect).normalize_identifier, copy=False)

Normalize all unquoted identifiers to either lower or upper case, depending on the dialect. This essentially makes those identifiers case-insensitive.

Note:

Some dialects (e.g. BigQuery) treat identifiers as case-insensitive even when they're quoted, so in these cases all identifiers are normalized.

Example:

>>> import sqlglot
>>> expression = sqlglot.parse_one('SELECT Bar.A AS A FROM "Foo".Bar')
>>> normalize_identifiers(expression).sql()
'SELECT bar.a AS a FROM "Foo".bar'
>>> normalize_identifiers("foo", dialect="snowflake").sql(dialect="snowflake")
'FOO'

Arguments:

expression: The expression to transform.
dialect: The dialect to use in order to decide how to normalize identifiers.

Returns:

The transformed expression.