Expr

Struct Expr 

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pub struct Expr { /* private fields */ }
Expand description

一个可组合的 SQL 片段表达式。

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impl Expr

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pub fn raw(sql: impl Into<String>) -> Self

直接插入一段 SQL 文本(不会变成参数)。

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pub fn true_() -> Self

创建一个恒为 TRUE 的表达式(TRUE)。

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pub fn false_() -> Self

创建一个恒为 FALSE 的表达式(FALSE)。

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pub fn push_raw(&mut self, sql: impl Into<String>)

追加 SQL 文本。

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pub fn push_arg(&mut self, v: impl Into<SqlValue>)

追加一个参数(构建时会生成占位符)。

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pub fn concat(self, other: Expr) -> Self

将当前表达式与另一个表达式连接(不自动添加空格)。

Trait Implementations§

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impl Clone for Expr

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fn clone(&self) -> Expr

Returns a duplicate of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for Expr

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl PartialEq for Expr

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fn eq(&self, other: &Expr) -> bool

Tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl StructuralPartialEq for Expr

Auto Trait Implementations§

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impl Freeze for Expr

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impl RefUnwindSafe for Expr

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impl Send for Expr

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impl Sync for Expr

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impl Unpin for Expr

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impl UnwindSafe for Expr

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<T> DynClone for T
where T: Clone,

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fn __clone_box(&self, _: Private) -> *mut ()

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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.