Transpiling date 'YYYY-MM-DD' into date 'YYYY-MM-DD'and not into cast('YYYY-MM-DD' AS DATE)

[evyasonov]

Is it a correct way to rewrite Generator.cast_sql the way it transpiles date 'YYYY-MM-DD' into date 'YYYY-MM-DD' and not into cast('YYYY-MM-DD' AS DATE)

    def cast_sql(self, expression: exp.Cast) -> str:
        this = self.sql(expression, 'this')
        to = self.sql(expression, 'to')

        if to and to.lower() in {'date', 'timestamp'} and isinstance(expression.this, exp.Literal) and expression.this.is_string:
            return f"{to.lower()} {self.sql(expression, 'this')}"
        else:
            return f"cast({this} AS {to})"

?

[tobymao]

i wouldn't do it like that, i would check to.this in DataType.TEMPORAL_TYPES

in the else case, call super().cast_sql

[tobymao]

instead of exp.Literal, you can just do expression.this.is_string

[evyasonov]

So this is final answer

    def cast_sql(self, expression: exp.Cast) -> str:
        if expression.to.this in exp.DataType.TEMPORAL_TYPES and expression.this.is_string:
            return f"{self.sql(expression, 'to').lower()} {self.sql(expression, 'this')}"
        return super().cast_sql(self, expression)

[tobymao]

something like this, you can tweak it to what you need it to do.

[evyasonov]

Thanks for the answers!

[tobymao]

You’re welcome.