Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Add support for FETCH cursor #510

Merged
merged 1 commit into from Jun 4, 2022
Merged

Add support for FETCH cursor #510

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
89 changes: 89 additions & 0 deletions src/ast/mod.rs
View file
Open in desktop
Expand Up @@ -895,6 +895,17 @@ pub enum Statement {
/// deleted along with the dropped table
purge: bool,
},
/// FETCH - retrieve rows from a query using a cursor
///
/// Note: this is a PostgreSQL-specific statement,
/// but may also compatible with other SQL.
Fetch {
/// Cursor name
name: Ident,
direction: FetchDirection,
/// Optional, It's possible to fetch rows form cursor to the table
into: Option<ObjectName>,
},
/// DISCARD [ ALL | PLANS | SEQUENCES | TEMPORARY | TEMP ]
///
/// Note: this is a PostgreSQL-specific statement,
Expand Down Expand Up @@ -1114,6 +1125,21 @@ impl fmt::Display for Statement {
write!(f, "{}", statement)
}
Statement::Query(s) => write!(f, "{}", s),
Statement::Fetch {
name,
direction,
into,
} => {
write!(f, "FETCH {} ", direction)?;

write!(f, "IN {}", name)?;

if let Some(into) = into {
write!(f, " INTO {}", into)?;
}

Ok(())
}
Statement::Directory {
overwrite,
local,
Expand Down Expand Up @@ -1859,6 +1885,69 @@ impl fmt::Display for Privileges {
}
}

/// Specific direction for FETCH statement
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub enum FetchDirection {
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

https://www.postgresql.org/docs/current/sql-fetch.html 👍

Count { limit: Value },
Next,
Prior,
First,
Last,
Absolute { limit: Value },
Relative { limit: Value },
All,
// FORWARD
// FORWARD count
Forward { limit: Option<Value> },
ForwardAll,
// BACKWARD
// BACKWARD count
Backward { limit: Option<Value> },
BackwardAll,
}

impl fmt::Display for FetchDirection {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
FetchDirection::Count { limit } => f.write_str(&limit.to_string())?,
FetchDirection::Next => f.write_str("NEXT")?,
FetchDirection::Prior => f.write_str("PRIOR")?,
FetchDirection::First => f.write_str("FIRST")?,
FetchDirection::Last => f.write_str("LAST")?,
FetchDirection::Absolute { limit } => {
f.write_str("ABSOLUTE ")?;
f.write_str(&limit.to_string())?;
}
FetchDirection::Relative { limit } => {
f.write_str("RELATIVE ")?;
f.write_str(&limit.to_string())?;
}
FetchDirection::All => f.write_str("ALL")?,
FetchDirection::Forward { limit } => {
f.write_str("FORWARD")?;

if let Some(l) = limit {
f.write_str(" ")?;
f.write_str(&l.to_string())?;
}
}
FetchDirection::ForwardAll => f.write_str("FORWARD ALL")?,
FetchDirection::Backward { limit } => {
f.write_str("BACKWARD")?;

if let Some(l) = limit {
f.write_str(" ")?;
f.write_str(&l.to_string())?;
}
}
FetchDirection::BackwardAll => f.write_str("BACKWARD ALL")?,
};

Ok(())
}
}

/// A privilege on a database object (table, sequence, etc.).
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
Expand Down
5 changes: 5 additions & 0 deletions src/keywords.rs
View file
Open in desktop
Expand Up @@ -67,6 +67,7 @@ macro_rules! define_keywords {
define_keywords!(
ABORT,
ABS,
ABSOLUTE,
ACTION,
ADD,
ALL,
Expand All @@ -93,6 +94,7 @@ define_keywords!(
AUTO_INCREMENT,
AVG,
AVRO,
BACKWARD,
BEGIN,
BEGIN_FRAME,
BEGIN_PARTITION,
Expand Down Expand Up @@ -238,6 +240,7 @@ define_keywords!(
FORCE_QUOTE,
FOREIGN,
FORMAT,
FORWARD,
FRAME_ROW,
FREE,
FREEZE,
Expand Down Expand Up @@ -386,6 +389,7 @@ define_keywords!(
PREPARE,
PRESERVE,
PRIMARY,
PRIOR,
PRIVILEGES,
PROCEDURE,
PROGRAM,
Expand Down Expand Up @@ -414,6 +418,7 @@ define_keywords!(
REGR_SXX,
REGR_SXY,
REGR_SYY,
RELATIVE,
RELEASE,
RENAME,
REPAIR,
Expand Down
62 changes: 62 additions & 0 deletions src/parser.rs
View file
Open in desktop
Expand Up @@ -167,6 +167,7 @@ impl<'a> Parser<'a> {
Keyword::CREATE => Ok(self.parse_create()?),
Keyword::DROP => Ok(self.parse_drop()?),
Keyword::DISCARD => Ok(self.parse_discard()?),
Keyword::FETCH => Ok(self.parse_fetch_statement()?),
Keyword::DELETE => Ok(self.parse_delete()?),
Keyword::INSERT => Ok(self.parse_insert()?),
Keyword::UPDATE => Ok(self.parse_update()?),
Expand Down Expand Up @@ -1824,6 +1825,67 @@ impl<'a> Parser<'a> {
})
}

// FETCH [ direction { FROM | IN } ] cursor INTO target;
pub fn parse_fetch_statement(&mut self) -> Result<Statement, ParserError> {
let direction = if self.parse_keyword(Keyword::NEXT) {
FetchDirection::Next
} else if self.parse_keyword(Keyword::PRIOR) {
FetchDirection::Prior
} else if self.parse_keyword(Keyword::FIRST) {
FetchDirection::First
} else if self.parse_keyword(Keyword::LAST) {
FetchDirection::Last
} else if self.parse_keyword(Keyword::ABSOLUTE) {
FetchDirection::Absolute {
limit: self.parse_number_value()?,
}
} else if self.parse_keyword(Keyword::RELATIVE) {
FetchDirection::Relative {
limit: self.parse_number_value()?,
}
} else if self.parse_keyword(Keyword::FORWARD) {
if self.parse_keyword(Keyword::ALL) {
FetchDirection::ForwardAll
} else {
FetchDirection::Forward {
// TODO: Support optional
limit: Some(self.parse_number_value()?),
}
}
} else if self.parse_keyword(Keyword::BACKWARD) {
if self.parse_keyword(Keyword::ALL) {
FetchDirection::BackwardAll
} else {
FetchDirection::Backward {
// TODO: Support optional
limit: Some(self.parse_number_value()?),
}
}
} else if self.parse_keyword(Keyword::ALL) {
FetchDirection::All
} else {
FetchDirection::Count {
limit: self.parse_number_value()?,
}
};

self.expect_one_of_keywords(&[Keyword::FROM, Keyword::IN])?;

let name = self.parse_identifier()?;

let into = if self.parse_keyword(Keyword::INTO) {
Some(self.parse_object_name()?)
} else {
None
};

Ok(Statement::Fetch {
name,
direction,
into,
})
}

pub fn parse_discard(&mut self) -> Result<Statement, ParserError> {
let object_type = if self.parse_keyword(Keyword::ALL) {
DiscardObject::ALL
Expand Down
24 changes: 24 additions & 0 deletions tests/sqlparser_postgres.rs
View file
Open in desktop
Expand Up @@ -1513,3 +1513,27 @@ fn parse_escaped_literal_string() {
"sql parser error: Unterminated encoded string literal at Line: 1, Column 8"
);
}

#[test]
fn parse_fetch() {
pg_and_generic().verified_stmt("FETCH 2048 IN \"SQL_CUR0x7fa44801bc00\"");
pg_and_generic().verified_stmt("FETCH 2048 IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic().verified_stmt("FETCH NEXT IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic().verified_stmt("FETCH PRIOR IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic().verified_stmt("FETCH FIRST IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic().verified_stmt("FETCH LAST IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic()
.verified_stmt("FETCH ABSOLUTE 2048 IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic()
.verified_stmt("FETCH RELATIVE 2048 IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic().verified_stmt("FETCH ALL IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic().verified_stmt("FETCH ALL IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic()
.verified_stmt("FETCH FORWARD 2048 IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic()
.verified_stmt("FETCH FORWARD ALL IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic()
.verified_stmt("FETCH BACKWARD 2048 IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
pg_and_generic()
.verified_stmt("FETCH BACKWARD ALL IN \"SQL_CUR0x7fa44801bc00\" INTO \"new_table\"");
}