Struct hdbconnect::Connection

pub struct Connection { /* fields omitted */ }

A synchronous connection to the database.

Methods

impl Connection

pub fn new<P: IntoConnectParams>(p: P) -> HdbResult<Self>

Factory method for authenticated connections.

Example

use hdbconnect::Connection;
let mut conn = Connection::new("hdbsql://my_user:my_passwd@the_host:2222").unwrap();

Errors

Several variants of HdbError can occur.

pub fn statement<S: AsRef<str>>(&mut self, stmt: S) -> HdbResult<HdbResponse>

Executes a statement on the database.

This generic method can handle all kinds of calls, and thus has the most generic return type. In many cases it will be more convenient to use one of the dedicated methods query(), dml(), exec() below, which internally convert the HdbResponse to the respective adequate simple result type.

Example

let mut response = connection.statement(&statement_string)?; // HdbResponse

Errors

Several variants of HdbError can occur.

pub fn query<S: AsRef<str>>(&mut self, stmt: S) -> HdbResult<ResultSet>

Executes a statement and expects a single ResultSet.

Should be used for query statements (like "SELECT ...") which return a single resultset.

Example

let mut rs = connection.query(&statement_string)?; // ResultSet

Errors

Several variants of HdbError can occur.

pub fn dml<S: AsRef<str>>(&mut self, stmt: S) -> HdbResult<usize>

Executes a statement and expects a single number of affected rows.

Should be used for DML statements only, i.e., INSERT, UPDATE, DELETE, UPSERT.

Example

let count = connection.dml(&statement_string)?; //usize

Errors

Several variants of HdbError can occur.

pub fn exec<S: AsRef<str>>(&mut self, stmt: S) -> HdbResult<()>

Executes a statement and expects a plain success.

Should be used for SQL commands like "ALTER SYSTEM ...".

Example

connection.exec(&statement_string)?;

Errors

Several variants of HdbError can occur.

pub fn prepare<S: AsRef<str>>(&self, stmt: S) -> HdbResult<PreparedStatement>

Prepares a statement and returns a handle (a PreparedStatement) to it.

Note that the PreparedStatement keeps using the same database connection as this Connection.

Example

let query_string = "select * from phrases where ID = ? and text = ?";
let mut statement = connection.prepare(query_string)?; //PreparedStatement

Errors

Several variants of HdbError can occur.

pub fn prepare_and_execute<S, T>(
    &self,
    stmt: S,
    input: &T
) -> HdbResult<HdbResponse> where
    S: AsRef<str>,
    T: Serialize, 

Prepares a statement and executes it a single time.

Errors

Several variants of HdbError can occur.

pub fn commit(&mut self) -> HdbResult<()>

Commits the current transaction.

Errors

Several variants of HdbError can occur.

pub fn rollback(&mut self) -> HdbResult<()>

Rolls back the current transaction.

Errors

Several variants of HdbError can occur.

pub fn spawn(&self) -> HdbResult<Self>

Creates a new connection object with the same settings and authentication.

Errors

Several variants of HdbError can occur.

pub fn multiple_statements_ignore_err<S: AsRef<str>>(&mut self, stmts: Vec<S>)

Utility method to fire a couple of statements, ignoring errors and return values.

Errors

Several variants of HdbError can occur.

pub fn multiple_statements<S: AsRef<str>>(
    &mut self,
    stmts: Vec<S>
) -> HdbResult<()>

Utility method to fire a couple of statements, ignoring their return values; the method returns with the first error, or with ().

Errors

Several variants of HdbError can occur.

pub fn pop_warnings(&self) -> HdbResult<Option<Vec<ServerError>>>

Returns warnings that were returned from the server since the last call to this method.

Errors

Only HdbError::Poison can occur.

pub fn set_auto_commit(&mut self, ac: bool) -> HdbResult<()>

Sets the connection's auto-commit behavior for future calls.

Errors

Only HdbError::Poison can occur.

pub fn is_auto_commit(&self) -> HdbResult<bool>

Returns the connection's auto-commit behavior.

Errors

Only HdbError::POóison can occur.

pub fn set_fetch_size(&mut self, fetch_size: u32) -> HdbResult<()>

Configures the connection's fetch size for future calls.

Errors

Only HdbError::Poison can occur.

pub fn get_lob_read_length(&self) -> HdbResult<u32>

Returns the connection's lob read length.

Errors

Only HdbError::Poison can occur.

pub fn set_lob_read_length(&mut self, l: u32) -> HdbResult<()>

Configures the connection's lob read length for future calls.

Errors

Only HdbError::Poison can occur.

pub fn get_lob_write_length(&self) -> HdbResult<usize>

Configures the connection's lob write length for future calls.

The intention of the parameter is to allow reducing the number of roundtrips to the database. Values smaller than rust's buffer size (8k) will have little effect, since each read() call to the Read impl in a HdbValue::LOBSTREAM will cause at most one write roundtrip to the database.

Errors

Only HdbError::Poison can occur.

pub fn set_lob_write_length(&mut self, l: usize) -> HdbResult<()>

Configures the connection's lob write length for future calls.

Errors

Only HdbError::Poison can occur.

pub fn id(&self) -> HdbResult<i32>

Returns the ID of the connection.

The ID is set by the server. Can be handy for logging.

Errors

Only HdbError::Poison can occur.

pub fn server_usage(&self) -> HdbResult<ServerUsage>

Provides information about the the server-side resource consumption that is related to this Connection object.

Errors

Only HdbError::Poison can occur.

pub fn get_call_count(&self) -> HdbResult<i32>

Returns the number of roundtrips to the database that have been done through this connection.

Errors

Only HdbError::Poison can occur.

pub fn set_application<S: AsRef<str>>(&self, application: S) -> HdbResult<()>

Sets client information into a session variable on the server.

Example:

connection.set_application("MyApp, built in rust")?;

Errors

Only HdbError::Poison can occur.

pub fn set_application_user<S: AsRef<str>>(&self, appl_user: S) -> HdbResult<()>

Sets client information into a session variable on the server.

Example:

connection.set_application_user("K2209657")?;

Errors

Only HdbError::Poison can occur.

pub fn set_application_version<S: AsRef<str>>(
    &mut self,
    version: S
) -> HdbResult<()>

Sets client information into a session variable on the server.

Example:

connection.set_application_version("5.3.23")?;

Errors

Only HdbError::Poison can occur.

pub fn set_application_source<S: AsRef<str>>(
    &mut self,
    source: S
) -> HdbResult<()>

Sets client information into a session variable on the server.

Example:

connection.set_application_source("update_customer.rs")?;

Errors

Only HdbError::Poison can occur.

pub fn get_resource_manager(&self) -> Box<dyn ResourceManager>

Returns an implementation of dist_tx::rm::ResourceManager that is based on this connection.

pub fn execute_with_debuginfo<S: AsRef<str>>(
    &mut self,
    stmt: S,
    module: S,
    line: i32
) -> HdbResult<HdbResponse>

Tools like debuggers can provide additional information while stepping through a source.

Errors

Several variants of HdbError can occur.

pub fn get_database_name(&self) -> HdbResult<Option<String>>

(MDC) Database name.

Errors

Only HdbError::Poison can occur.

pub fn get_system_id(&self) -> HdbResult<Option<String>>

The system id is set by the server with the SAPSYSTEMNAME of the connected instance (for tracing and supportability purposes).

Errors

Only HdbError::Poison can occur.

pub fn client_info(&self) -> HdbResult<Vec<(String, String)>>

Returns the information that is given to the server as client context.

Errors

Only HdbError::Poison can occur.

pub fn connect_string(&self) -> HdbResult<String>

Returns a connect url (excluding the password) that reflects the options that were used to establish this connection.

Errors

Only HdbError::Poison can occur.

pub fn get_full_version_string(&self) -> HdbResult<Option<String>>

HANA Full version string.

Errors

Only HdbError::Poison can occur.

Trait Implementations

impl Clone for Connection

fn clone(&self) -> Connection

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Connection

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

Formats the value using the given formatter.