/// <param name = "isolationLevel">
/// Only SQL standard isolation levels are supported, except
/// <see cref = "IsolationLevel.Snapshot" />.
/// </param>
/// <exception cref = "SqlException" />
/// <exception cref = "OperationCanceledException" />
public static ValueTask SetIsolationLevel
(this ISqlTransaction transaction, IsolationLevel isolationLevel, CancellationToken ct = default)
{
var sql =
isolationLevel switch {
IsolationLevel.ReadUncommitted => setReadUncommittedSql,
IsolationLevel.ReadCommitted => setReadCommittedSql,
IsolationLevel.RepeatableRead => setRepeatableReadSql,
IsolationLevel.Serializable => setSerializableSql,
IsolationLevel.Unspecified =>
throw new ArgumentException(
"Transaction has no specified isolation level.",
nameof(transaction)),
IsolationLevel.Snapshot =>
throw new ArgumentException(
"Snapshot isolation level cannot be set by this method.",
nameof(transaction)),
_ =>
throw new ArgumentException(
$"Isolation level {isolationLevel} is not part of SQL standard.",
nameof(transaction))
};
return(transaction.ExecuteAsync(sql, ct));
}
}
/// <exception cref = "SqlException" />
/// <exception cref = "OperationCanceledException" />
public static ValueTask SetAccessAsync
(this ISqlTransaction transaction, SqlAccess access, CancellationToken ct = default)
{
var sql = access switch { SqlAccess.Rw => setRwSql, SqlAccess.Ro => setRoSql };
return(transaction.ExecuteAsync(sql, ct));
}
const String setReadUncommittedSql = "set transaction isolation level read uncommitted";
/// <exception cref = "SqlException" />
/// <exception cref = "OperationCanceledException" />
public static ValueTask SetRoAsync
(this ISqlTransaction transaction, CancellationToken cancellationToken = default) =>
transaction.ExecuteAsync(setRoSql, cancellationToken);
/// <exception cref = "SqlException" /> /// <exception cref = "OperationCanceledException" /> public static ValueTask SetSerializable(this ISqlTransaction transaction, CancellationToken ct = default) => transaction.ExecuteAsync(setSerializableSql, ct);
/// <exception cref = "SqlException" /> /// <exception cref = "OperationCanceledException" /> public static ValueTask SetRepeatableRead(this ISqlTransaction transaction, CancellationToken ct = default) => transaction.ExecuteAsync(setRepeatableReadSql, ct);