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Improve formatting

Olivier Mengué 2020-02-28 11:35:44 +01:00
parent df33a22130
commit e572ac21bd
1 changed files with 13 additions and 10 deletions
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23
SQLInterface.md

@ -36,11 +36,12 @@ if err := db.PingContext(ctx); err != nil {
}
```
After use, the database is closed using `Close`.
After use, the database is closed using [`Close`](https://golang.org/pkg/database/sql/#DB.Close).
# Executing queries
ExecContext is used for queries where no rows are returned:
[`ExecContext`](https://golang.org/pkg/database/sql/#DB.ExecContext)
is used for queries where no rows are returned:
```go
result, err := db.ExecContext(ctx,
@ -54,7 +55,8 @@ Where result contains the last insert ID and number of
rows affected. The availability of these values is dependent on
the database driver.
QueryContext is used for retrieval:
[`QueryContext`](https://golang.org/pkg/database/sql/#DB.QueryContext)
is used for retrieval:
```go
rows, err := db.QueryContext(ctx, "SELECT name FROM users WHERE age = $1", age)
@ -74,14 +76,15 @@ if err := rows.Err(); err != nil {
}
```
QueryRowContext is used where only a single row is expected:
[`QueryRowContext`](https://golang.org/pkg/database/sql/#DB.QueryRowContext)
is used where only a single row is expected:
```go
var age int64
err := db.QueryRowContext(ctx, "SELECT age FROM users WHERE name = $1", name).Scan(&age)
```
Prepared statements can be created with Prepare:
Prepared statements can be created with [`PrepareContext`](https://golang.org/pkg/database/sql/#DB.PrepareContext):
```go
age := 27
@ -93,12 +96,12 @@ rows, err := stmt.Query(age)
// process rows
```
ExecContext, QueryContext and QueryRowContext can be called on statements. After use, a
statement should be closed with Close.
[`ExecContext`](https://golang.org/pkg/database/sql/#Stmt.ExecContext), [`QueryContext`](https://golang.org/pkg/database/sql/#Stmt.QueryContext) and [`QueryRowContext`](https://golang.org/pkg/database/sql/#Stmt.QueryContext) can be called on statements. After use, a
statement should be closed with [`Close`](https://golang.org/pkg/database/sql/#Stmt.Close).
# Transactions
Transactions are started with Begin:
Transactions are started with [`BeginTx`](https://golang.org/pkg/database/sql/#DB.BeginTx):
```go
tx, err := db.BeginTx(ctx, nil)
@ -107,10 +110,10 @@ if err != nil {
}
```
The ExecContext, QueryContext, QueryRowContext and PrepareContext functions already covered can be
The [`ExecContext`](https://golang.org/pkg/database/sql/#Tx.ExecContext), [`QueryContext`](https://golang.org/pkg/database/sql/#Tx.QueryContext), [`QueryRowContext`](https://golang.org/pkg/database/sql/#Tx.QueryRowContext) and [`PrepareContext`](https://golang.org/pkg/database/sql/#Tx.PrepareContext) methods already covered can be
used in a transaction.
A transaction must end with a call to Commit or Rollback.
A transaction must end with a call to [`Commit`](https://golang.org/pkg/database/sql/#Tx.Commit) or [`Rollback`](https://golang.org/pkg/database/sql/#Tx.Rollback).
# Dealing with NULL