sqlx_core/
database.rs

1//! Traits to represent a database driver.
2//!
3//! # Support
4//!
5//! ## Tier 1
6//!
7//! Tier 1 support can be thought of as "guaranteed to work". Automated testing is setup to
8//! ensure a high level of stability and functionality.
9//!
10//! | Database | Version | Driver |
11//! | - | - | - |
12//! | [MariaDB] | 10.1+ | [`mysql`] |
13//! | [Microsoft SQL Server] | 2019 | [`mssql`] (Pending a full rewrite) |
14//! | [MySQL] | 5.6, 5.7, 8.0 | [`mysql`] |
15//! | [PostgreSQL] | 9.5+ | [`postgres`] |
16//! | [SQLite] | 3.20.1+ | [`sqlite`] |
17//!
18//! [MariaDB]: https://mariadb.com/
19//! [MySQL]: https://www.mysql.com/
20//! [Microsoft SQL Server]: https://www.microsoft.com/en-us/sql-server
21//! [PostgreSQL]: https://www.postgresql.org/
22//! [SQLite]: https://www.sqlite.org/
23//!
24//! [`mysql`]: crate::mysql
25//! [`postgres`]: crate::postgres
26//! [`mssql`]: crate::mssql
27//! [`sqlite`]: crate::sqlite
28//!
29//! ## Tier 2
30//!
31//! Tier 2 support can be thought as "should work". No specific automated testing is done,
32//! at this time, but there are efforts to ensure compatibility. Tier 2 support also includes
33//! database distributions that provide protocols that closely match a database from Tier 1.
34//!
35//! _No databases are in tier 2 at this time._
36//!
37//! # `Any`
38//!
39//! Selecting a database driver is, by default, a compile-time decision. SQLx is designed this way
40//! to take full advantage of the performance and type safety made available by Rust.
41//!
42//! We recognize that you may wish to make a runtime decision to decide the database driver. The
43//! [`Any`](crate::any) driver is provided for that purpose.
44//!
45//! ## Example
46//!
47//! ```rust,ignore
48//! // connect to SQLite
49//! let conn = AnyConnection::connect("sqlite://file.db").await?;
50//!
51//! // connect to Postgres, no code change
52//! // required, decided by the scheme of the URL
53//! let conn = AnyConnection::connect("postgres://localhost/sqlx").await?;
54//! ```
55
56use std::fmt::Debug;
57
58use crate::arguments::Arguments;
59use crate::column::Column;
60use crate::connection::Connection;
61use crate::row::Row;
62
63use crate::statement::Statement;
64use crate::transaction::TransactionManager;
65use crate::type_info::TypeInfo;
66use crate::value::{Value, ValueRef};
67
68/// A database driver.
69///
70/// This trait encapsulates a complete set of traits that implement a driver for a
71/// specific database (e.g., MySQL, PostgreSQL).
72pub trait Database: 'static + Sized + Send + Debug {
73    /// The concrete `Connection` implementation for this database.
74    type Connection: Connection<Database = Self>;
75
76    /// The concrete `TransactionManager` implementation for this database.
77    type TransactionManager: TransactionManager<Database = Self>;
78
79    /// The concrete `Row` implementation for this database.
80    type Row: Row<Database = Self>;
81
82    /// The concrete `QueryResult` implementation for this database.
83    type QueryResult: 'static + Sized + Send + Sync + Default + Extend<Self::QueryResult>;
84
85    /// The concrete `Column` implementation for this database.
86    type Column: Column<Database = Self>;
87
88    /// The concrete `TypeInfo` implementation for this database.
89    type TypeInfo: TypeInfo;
90
91    /// The concrete type used to hold an owned copy of the not-yet-decoded value that was
92    /// received from the database.
93    type Value: Value<Database = Self> + 'static;
94    /// The concrete type used to hold a reference to the not-yet-decoded value that has just been
95    /// received from the database.
96    type ValueRef<'r>: ValueRef<'r, Database = Self>;
97
98    /// The concrete `Arguments` implementation for this database.
99    type Arguments<'q>: Arguments<'q, Database = Self>;
100    /// The concrete type used as a buffer for arguments while encoding.
101    type ArgumentBuffer<'q>;
102
103    /// The concrete `Statement` implementation for this database.
104    type Statement<'q>: Statement<'q, Database = Self>;
105
106    /// The display name for this database driver.
107    const NAME: &'static str;
108
109    /// The schemes for database URLs that should match this driver.
110    const URL_SCHEMES: &'static [&'static str];
111}
112
113/// A [`Database`] that maintains a client-side cache of prepared statements.
114pub trait HasStatementCache {}
sqlx_core/database.rs

sqlx_core/
database.rs
