Interfaces · 5 min read

IDbSetting

This interface is used to mark a class to be a database setting object. It allows you to control the behavior of the library on a specific RDBMS data provider based on the value you provided on the…

Properties

Below is the list of properties.

Name	Description
AreTableHintsSupported	Gets the value that indicates whether the table hints are supported.
ClosingQuote	Gets the character used for closing quote.
AverageableType	Gets the default averageable .NET CLR types for the database.
DefaultSchema	Gets the default schema of the database.
IsAffectedRowsSupported	Gets a value that indicates whether the current DB Provider supports returning the number of affected rows from the execution of a non-query command.
IsDirectionSupported	Gets a value that indicates whether setting the value of `DbParameter.Direction` object is supported.
IsExecuteReaderDisposable	Gets a value that indicates whether the `DbCommand` object must be disposed after calling the `DbCommand.ExecuteReader()` method.
IsInsertAllBatchable	Gets a nullable value that overrides `IsMultiStatementExecutable` specifically for whether InsertAll can batch more than one row into a single statement (a genuine multi-row `VALUES (...), (...), ...` list, not multiple `;`-separated statements). Left unset (`null`) by default, which falls back to `IsMultiStatementExecutable`. Set this when a provider supports a real multi-row `VALUES` list without supporting arbitrary compound statements.
IsMultiStatementExecutable	Gets a value whether the multiple statement execution is supported.
IsPreparable	Gets a value that indicates whether the current DB Provider supports the `DbCommand.Prepare()` calls.
IsTransactionSupported	Gets a value that indicates whether the current DB Provider supports the transaction objects.
IsUseUpsert	Gets a value that indicates whether the Insert/Update operation will be used for Merge operation.
MaxParameterCount	Gets the maximum number of parameters/members the current DB provider allows in a single generated command text — most directly, the number of values a single `WHERE column IN (...)` clause can hold. Operations that batch a large key list into that shape (e.g. `DeleteAll(keys)`) split it into chunks no larger than this value before generating each chunk’s command text. Defaults to `2098` (SQL Server’s ~2100 parameter ceiling, minus a small safety margin).
MultiStatementSeparator	Gets the string used to join the individual command texts generated by the QueryMultiple and `QueryMultipleAsync` operations into a single command text.
OpeningQuote	Gets the character used for opening quote.
ParameterPrefix	Gets the character used for the database command parameter prefixing.
RequiresDbTypeBeforeValue	Gets a value that indicates whether `DbParameter.DbType` must be assigned (inferred from the value’s CLR type, if not explicitly given) before `DbParameter.Value` is set. Some providers lazily initialize internal parameter state inside the `DbType` setter and throw if `Value` is set first on a parameter fresh off `DbCommand.CreateParameter()`. Defaults to `false`.
SkipsUnreferencedParameters	Gets a value that indicates whether the current DB Provider strictly validates that every parameter bound to the command is actually referenced by a placeholder in the generated `DbCommand.CommandText`, throwing when a bound parameter has no corresponding placeholder. A null-valued equality filter (e.g. `WHERE "Id" = @Id` with a `null` value) is rendered by QueryField as the literal `"Id" IS NULL` with no `@Id` placeholder at all, yet the parameter is still normally bound — most providers silently tolerate the unused parameter, but a strict provider rejects the whole command. When `true`, such unreferenced parameters are skipped instead of bound. Defaults to `false`.
SqlTextParameterPrefix	Gets the character used for prefixing a parameter when it is embedded within a raw/text SQL statement, as opposed to when it is bound as a `DbParameter` object.

How to Implement?

You have to manually create a class that implements this interface.

public class MyCustomSqlServerDbSetting : IDbSetting
{
    public bool AreTableHintsSupported { get; set; } = true;
    public string ClosingQuote { get; set; } = "]";
    public Type AverageableType { get; set; } = typeof(double);
    public string DefaultSchema { get; set; } = "dbo";
    public bool IsAffectedRowsSupported { get; set; } = true;
    public bool IsDirectionSupported { get; set; } = true;
    public bool IsExecuteReaderDisposable { get; set; } = true;
    public bool? IsInsertAllBatchable { get; set; } = null;
    public bool IsMultiStatementExecutable { get; set; } = true;
    public bool IsPreparable { get; set; } = true;
    public bool IsTransactionSupported { get; set; } = true;
    public bool IsUseUpsert { get; set; } = false;
    public int MaxParameterCount { get; set; } = 2098;
    public string MultiStatementSeparator { get; set; } = ";";
    public string OpeningQuote { get; set; } = "[";
    public string ParameterPrefix { get; set; } = "@";
    public bool RequiresDbTypeBeforeValue { get; set; } = false;
    public bool SkipsUnreferencedParameters { get; set; } = false;
    public string SqlTextParameterPrefix { get; set; } = "@";
}

Please see the more detailed implementations at Database Setting page.

GetHashCode

You have to override the implementation of the GetHashCode() based on the combinations of the properties.

The reason to this, the library is using the equality based on the generated hashcode. Failure to comply may trigger a performance problem in your application.

We recommend to instead use the BaseDbSetting class when implementing a customized database setting.

Usability

Once the class has been implemented, you have to call the DbSettingMapper class for mappings (per RDBMS data provider).

DbSettingMapper.Add(typeof(SqlConnection), new CustomSqlServerDbSetting(), true);