Struct extremedb::sql::value::Ref

pub struct Ref<'a> { /* fields omitted */ }

An SQL value reference.

In addition to the value itself, a value reference holds a reference to the value's allocator, making it possible to release the value when the reference goes out of scope.

Methods from Deref<Target = Value<'a>>

pub fn value_type(&self) -> Result<Type>

Returns the type of the contained value.

pub fn size(&self) -> Result<usize>

For non-scalar types, returns the size of the data.

Depending on the contained type, returns:

• String and Binary: length of the string or binary string;
• Array: number of elements.

pub fn is_null(&self) -> bool

Returns true if the value is an SQL null value.

pub fn is_true(&self) -> bool

Returns true if the value is a boolean true value, or a non-zero integer.

pub fn to_i64(&self) -> Result<i64>

Casts the value to i64.

Strings are parsed and converted, if possible; otherwise an error is returned.

pub fn to_real(&self) -> Result<f64>

Casts the value to f64.

Strings are parsed and converted, if possible; otherwise an error is returned.

pub fn to_date_time(&self) -> Result<u64>

Casts the value to the number of system ticks elapsed since the beginning of the epoch.

String values are parsed using strptime() where available, or a compatible custom function.

pub fn to_system_time(&self) -> Result<SystemTime>

Casts the value to the number of system ticks elapsed since the beginning of the epoch, and converts the resulting value to std::time::SystemTime.

pub fn to_numeric(&self) -> Result<Numeric>

Returns the contained fixed-width numeric value, if any, or an error.

pub fn to_string(&self) -> Result<String>

Converts the value to the string representation.

pub fn as_str(&self) -> Result<&str>

Returns a string slice pointing to the contents of a String value, or an error if the value is not a String.

pub fn to_binary(&self) -> Result<Vec<u8>>

Returns a copy of the bytes of a string or a binary value.

pub fn as_bytes(&self) -> Result<&[u8]>

Returns a byte slice pointing to the contents of a Binary value, or an error if the value is not a Binary.

pub fn as_array(&self) -> Result<&Array<'_>>

Casts the value to Array if it has the Array type; returns an error otherwise.

pub fn as_sequence(&self) -> Result<&Sequence<'_>>

Casts the value to Sequence if it has the Sequence type; returns an error otherwise.

pub fn as_blob(&self) -> Result<&Blob<'_>>

Casts the value to Blob if it has the Blob type; returns an error otherwise.

Trait Implementations

impl<'a> Deref for Ref<'a>

type Target = Value<'a>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'a> Drop for Ref<'a>

fn drop(&mut self)

Executes the destructor for this type.