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|This is an Oracle database driver for Rust based on ODPI-C.
Applications using Rust-oracle 0.1.x should use 0.2.x. The incompatibility between 0.1.x and 0.2.x is trivial so they will work well without modification. The author continues updating 0.2.x to fix bugs as long as it doesn't introduce incompatibilities.
New features are added in Rust-oracle 0.3.x or later. There are enormous
incompatibilities between 0.2.x and 0.3.x. They were introduced to follow
Rust way. Some parameters were removed and builder data types were added
instead. Some types were moved to a submodule sql_type.
Rust-oracle 0.4.x will include breaking changes about query methods.
The query methods with as may be renamed to and merged into methods
without as. The params argument of Connection.prepare will be
replaced with some kind of the builder pattern.
See ChangeLog.md.
Compile-time Requirements in this document.Put this in your Cargo.toml:
text
[dependencies]
oracle = "0.3.0"
When you need to fetch or bind chrono
data types, enable chrono feature:
text
[dependencies]
oracle = { version = "0.3.0", features = ["chrono"] }
Then put this in your crate root:
rust
extern crate oracle;
Executes select statements and get rows:
```rust use oracle::{Connection, Error};
// Connect to a database. let conn = Connection::connect("scott", "tiger", "//localhost/XE")?;
let sql = "select ename, sal, comm from emp where deptno = :1";
// Select a table with a bind variable.
println!("---------------|---------------|---------------|");
let rows = conn.query(sql, &[&30])?;
for rowresult in rows {
let row = rowresult?;
// get a column value by position (0-based)
let ename: String = row.get(0)?;
// get a column by name (case-insensitive)
let sal: i32 = row.get("sal")?;
// Use Option<...> to get a nullable column.
// Otherwise, Err(Error::NullValue) is returned
// for null values.
let comm: Option
println!(" {:14}| {:>10} | {:>10} |",
ename,
sal,
comm.map_or("".to_string(), |v| v.to_string()));
}
// Another way to fetch rows.
// The rows iterator returns Result<(String, i32, Option
Executes select statements and get the first rows:
```rust use oracle::Connection;
// Connect to a database. let conn = Connection::connect("scott", "tiger", "//localhost/XE")?;
let sql = "select ename, sal, comm from emp where empno = :1";
// Print the first row.
let row = conn.queryrow(sql, &[&7369])?;
let ename: String = row.get("empno")?;
let sal: i32 = row.get("sal")?;
let comm: OptionErr(Error::NoDataFound).
// Get the first row as a tupple
let row = conn.queryrowas::<(String, i32, Option
Executes non-select statements:
```rust use oracle::Connection;
// Connect to a database. let conn = Connection::connect("scott", "tiger", "//localhost/XE")?;
conn.execute("create table person (id number(38), name varchar2(40))", &[])?;
// Execute a statement with positional parameters. conn.execute("insert into person values (:1, :2)", &[&1, // first parameter &"John" // second parameter ])?;
// Execute a statement with named parameters. conn.execute_named("insert into person values (:id, :name)", &[("id", &2), // 'id' parameter ("name", &"Smith"), // 'name' parameter ])?;
// Commit the transaction. conn.commit()?;
// Delete rows conn.execute("delete from person", &[])?;
// Rollback the transaction. conn.rollback()?; ```
Prints column information:
```rust use oracle::Connection;
// Connect to a database. let conn = Connection::connect("scott", "tiger", "//localhost/XE")?;
let sql = "select ename, sal, comm from emp where 1 = 2"; let rows = conn.query(sql, &[])?;
// Print column names for info in rows.column_info() { print!(" {:14}|", info.name()); } println!("");
// Print column types for info in rows.columninfo() { print!(" {:14}|", info.oracletype().to_string()); } println!(""); ```
Prepared statement:
```rust use oracle::Connection;
let conn = Connection::connect("scott", "tiger", "//localhost/XE")?;
// Create a prepared statement let mut stmt = conn.prepare("insert into person values (:1, :2)", &[])?; // Insert one row stmt.execute(&[&1, &"John"])?; // Insert another row stmt.execute(&[&2, &"Smith"])?; ```
This is more efficient than two conn.execute().
An SQL statement is executed in the DBMS as follows:
When a prepared statement is used, step 1 is called only once.
NLS_LANG consists of three components: language, territory and charset. However the charset component is ignored and UTF-8(AL32UTF8) is used as charset because rust characters are UTF-8.
The territory component specifies numeric format, date format and so on. However it affects only conversion in Oracle. See the following example:
```rust use oracle::Connection;
// The territory is France. std::env::setvar("NLSLANG", "french_france.AL32UTF8"); let conn = Connection::connect("scott", "tiger", "")?;
// 10.1 is converted to a string in Oracle and fetched as a string.
let result = conn.queryrowas::
// 10.1 is fetched as a number and converted to a string in rust-oracle
let result = conn.queryrowas::
Note that NLS_LANG must be set before first rust-oracle function execution if required.
Rust-oracle and ODPI-C bundled in rust-oracle are under the terms of: