jet/wiki/Statements.md

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Following statements are supported:
* [SELECT](https://github.com/go-jet/jet/wiki/SELECT)
* [INSERT](https://github.com/go-jet/jet/wiki/INSERT)
* [UPDATE](https://github.com/go-jet/jet/wiki/UPDATE)
* [DELETE](https://github.com/go-jet/jet/wiki/DELETE)
* [LOCK](https://github.com/go-jet/jet/wiki/LOCK)
_This list might be extended with feature Jet releases._
Statements SQL can be debugged in two ways:
- `Sql() (query string, args []interface{}, err error)` - retrieves parametrized sql query with list of arguments
- `DebugSql() (query string, err error)` - retrieves debug query where every parametrized placeholder is replaced with its argument.
Statements can be executed by following methods:
- `Query(db execution.DB, destination interface{}) error` - executes statements over database connection db and stores row result in destination.
- `QueryContext(db execution.DB, context context.Context, destination interface{}) error` - executes statement with a context over database connection db and stores row result in destination.
- `Exec(db execution.DB) (sql.Result, error)` - executes statement over db connection without returning any rows.
- `ExecContext(db execution.DB, context context.Context) (sql.Result, error)` - executes statement with context over db connection without returning any rows.
Each execution method first creates parametrized sql query with list of arguments and then initiates query on database connection.
Exec and ExecContext are just a wrappers around database `Exec` and `ExecContext`.
`Query` and `QueryContext` are bit more complex, the are wrappers around database `Query` and `QueryContext`,
but they also perform grouping of row result to arbitrary `destination` structure.
Database connection can be of any type that implements following interface:
```go
type DB interface {
Exec(query string, args ...interface{}) (sql.Result, error)
ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error)
Query(query string, args ...interface{}) (*sql.Rows, error)
QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)
}
```
These include but are not limited to:
- `sql.DB`
- `sql.Tx`
- `sql.Conn`