Trait diesel::expression_methods::TextExpressionMethods [−][src]
pub trait TextExpressionMethods: Expression + Sized {
fn concat<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> Concat<Self, T::Expression> { ... }
fn like<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> Like<Self, T::Expression> { ... }
fn not_like<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> NotLike<Self, T::Expression> { ... }
}
Expand description
Methods present on text expressions
Provided methods
fn concat<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> Concat<Self, T::Expression>
fn concat<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> Concat<Self, T::Expression>
Concatenates two strings using the ||
operator.
Example
let names = users.select(name.concat(" the Greatest")).load(&connection);
let expected_names = vec![
"Sean the Greatest".to_string(),
"Tess the Greatest".to_string(),
];
assert_eq!(Ok(expected_names), names);
// If the value is nullable, the output will be nullable
let names = users.select(hair_color.concat("ish")).load(&connection);
let expected_names = vec![
Some("Greenish".to_string()),
None,
];
assert_eq!(Ok(expected_names), names);
fn like<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> Like<Self, T::Expression>
fn like<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> Like<Self, T::Expression>
Returns a SQL LIKE
expression
This method is case insensitive for SQLite and MySQL.
On PostgreSQL, LIKE
is case sensitive. You may use
ilike()
for case insensitive comparison on PostgreSQL.
Examples
let starts_with_s = users
.select(name)
.filter(name.like("S%"))
.load::<String>(&connection)?;
assert_eq!(vec!["Sean"], starts_with_s);
fn not_like<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> NotLike<Self, T::Expression>
fn not_like<T: AsExpression<Self::SqlType>>(
self,
other: T
) -> NotLike<Self, T::Expression>
Returns a SQL NOT LIKE
expression
This method is case insensitive for SQLite and MySQL.
On PostgreSQL NOT LIKE
is case sensitive. You may use
not_ilike()
for case insensitive comparison on PostgreSQL.
Examples
let doesnt_start_with_s = users
.select(name)
.filter(name.not_like("S%"))
.load::<String>(&connection)?;
assert_eq!(vec!["Tess"], doesnt_start_with_s);