This is an automated email from the ASF dual-hosted git repository.
alamb pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/datafusion.git
The following commit(s) were added to refs/heads/main by this push:
new 827d0e3a29 Add dialect param to use double precision for float64 in
Postgres (#11495)
827d0e3a29 is described below
commit 827d0e3a29c0ea34bafbf03f5102407bd8e9b826
Author: Qianqian <[email protected]>
AuthorDate: Fri Jul 19 13:23:32 2024 -0700
Add dialect param to use double precision for float64 in Postgres (#11495)
* Add dialect param to use double precision for float64 in Postgres
* return ast data type instead of bool
* Fix errors in merging
* fix
---
datafusion/sql/src/unparser/dialect.rs | 28 ++++++++++++++++++++++++++++
datafusion/sql/src/unparser/expr.rs | 30 +++++++++++++++++++++++++++++-
2 files changed, 57 insertions(+), 1 deletion(-)
diff --git a/datafusion/sql/src/unparser/dialect.rs
b/datafusion/sql/src/unparser/dialect.rs
index 1e82fc2b3c..ed0cfddc38 100644
--- a/datafusion/sql/src/unparser/dialect.rs
+++ b/datafusion/sql/src/unparser/dialect.rs
@@ -46,11 +46,18 @@ pub trait Dialect: Send + Sync {
IntervalStyle::PostgresVerbose
}
+ // Does the dialect use DOUBLE PRECISION to represent Float64 rather than
DOUBLE?
+ // E.g. Postgres uses DOUBLE PRECISION instead of DOUBLE
+ fn float64_ast_dtype(&self) -> sqlparser::ast::DataType {
+ sqlparser::ast::DataType::Double
+ }
+
// The SQL type to use for Arrow Utf8 unparsing
// Most dialects use VARCHAR, but some, like MySQL, require CHAR
fn utf8_cast_dtype(&self) -> ast::DataType {
ast::DataType::Varchar(None)
}
+
// The SQL type to use for Arrow LargeUtf8 unparsing
// Most dialects use TEXT, but some, like MySQL, require CHAR
fn large_utf8_cast_dtype(&self) -> ast::DataType {
@@ -98,6 +105,10 @@ impl Dialect for PostgreSqlDialect {
fn interval_style(&self) -> IntervalStyle {
IntervalStyle::PostgresVerbose
}
+
+ fn float64_ast_dtype(&self) -> sqlparser::ast::DataType {
+ sqlparser::ast::DataType::DoublePrecision
+ }
}
pub struct MySqlDialect {}
@@ -137,6 +148,7 @@ pub struct CustomDialect {
supports_nulls_first_in_sort: bool,
use_timestamp_for_date64: bool,
interval_style: IntervalStyle,
+ float64_ast_dtype: sqlparser::ast::DataType,
utf8_cast_dtype: ast::DataType,
large_utf8_cast_dtype: ast::DataType,
}
@@ -148,6 +160,7 @@ impl Default for CustomDialect {
supports_nulls_first_in_sort: true,
use_timestamp_for_date64: false,
interval_style: IntervalStyle::SQLStandard,
+ float64_ast_dtype: sqlparser::ast::DataType::Double,
utf8_cast_dtype: ast::DataType::Varchar(None),
large_utf8_cast_dtype: ast::DataType::Text,
}
@@ -182,6 +195,10 @@ impl Dialect for CustomDialect {
self.interval_style
}
+ fn float64_ast_dtype(&self) -> sqlparser::ast::DataType {
+ self.float64_ast_dtype.clone()
+ }
+
fn utf8_cast_dtype(&self) -> ast::DataType {
self.utf8_cast_dtype.clone()
}
@@ -210,6 +227,7 @@ pub struct CustomDialectBuilder {
supports_nulls_first_in_sort: bool,
use_timestamp_for_date64: bool,
interval_style: IntervalStyle,
+ float64_ast_dtype: sqlparser::ast::DataType,
utf8_cast_dtype: ast::DataType,
large_utf8_cast_dtype: ast::DataType,
}
@@ -227,6 +245,7 @@ impl CustomDialectBuilder {
supports_nulls_first_in_sort: true,
use_timestamp_for_date64: false,
interval_style: IntervalStyle::PostgresVerbose,
+ float64_ast_dtype: sqlparser::ast::DataType::Double,
utf8_cast_dtype: ast::DataType::Varchar(None),
large_utf8_cast_dtype: ast::DataType::Text,
}
@@ -238,6 +257,7 @@ impl CustomDialectBuilder {
supports_nulls_first_in_sort: self.supports_nulls_first_in_sort,
use_timestamp_for_date64: self.use_timestamp_for_date64,
interval_style: self.interval_style,
+ float64_ast_dtype: self.float64_ast_dtype,
utf8_cast_dtype: self.utf8_cast_dtype,
large_utf8_cast_dtype: self.large_utf8_cast_dtype,
}
@@ -273,6 +293,14 @@ impl CustomDialectBuilder {
self
}
+ pub fn with_float64_ast_dtype(
+ mut self,
+ float64_ast_dtype: sqlparser::ast::DataType,
+ ) -> Self {
+ self.float64_ast_dtype = float64_ast_dtype;
+ self
+ }
+
pub fn with_utf8_cast_dtype(mut self, utf8_cast_dtype: ast::DataType) ->
Self {
self.utf8_cast_dtype = utf8_cast_dtype;
self
diff --git a/datafusion/sql/src/unparser/expr.rs
b/datafusion/sql/src/unparser/expr.rs
index 950e7e1128..2f7854c1a1 100644
--- a/datafusion/sql/src/unparser/expr.rs
+++ b/datafusion/sql/src/unparser/expr.rs
@@ -1240,7 +1240,7 @@ impl Unparser<'_> {
not_impl_err!("Unsupported DataType: conversion:
{data_type:?}")
}
DataType::Float32 => Ok(ast::DataType::Float(None)),
- DataType::Float64 => Ok(ast::DataType::Double),
+ DataType::Float64 => Ok(self.dialect.float64_ast_dtype()),
DataType::Timestamp(_, tz) => {
let tz_info = match tz {
Some(_) => TimezoneInfo::WithTimeZone,
@@ -1822,6 +1822,34 @@ mod tests {
Ok(())
}
+ #[test]
+ fn custom_dialect_float64_ast_dtype() -> Result<()> {
+ for (float64_ast_dtype, identifier) in [
+ (sqlparser::ast::DataType::Double, "DOUBLE"),
+ (
+ sqlparser::ast::DataType::DoublePrecision,
+ "DOUBLE PRECISION",
+ ),
+ ] {
+ let dialect = CustomDialectBuilder::new()
+ .with_float64_ast_dtype(float64_ast_dtype)
+ .build();
+ let unparser = Unparser::new(&dialect);
+
+ let expr = Expr::Cast(Cast {
+ expr: Box::new(col("a")),
+ data_type: DataType::Float64,
+ });
+ let ast = unparser.expr_to_sql(&expr)?;
+
+ let actual = format!("{}", ast);
+
+ let expected = format!(r#"CAST(a AS {identifier})"#);
+ assert_eq!(actual, expected);
+ }
+ Ok(())
+ }
+
#[test]
fn customer_dialect_support_nulls_first_in_ort() -> Result<()> {
let tests: Vec<(Expr, &str, bool)> = vec![
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
