Class AdbTypeMapper

Stores mappings between .NET types and database types, and allows setting the database type of database parameters from these mappings. Many mappings to provider-independent DbType database types are common across database providers, while other mappings are specific to each provider.

To create a new type mapper, inherit from this class and set mappings in the constructor.

When the database type is known at compile time, the user or worker should set it explicitly. The mappings are instead used when the database type is only known at runtime, by automatically setting it with SetMappedType(AdbParameter, Type, AdbColumnSchema, ParameterDirection).

Note that the .NET type name is specified as the compact display name returned by DisplayName(Type).

Also see predefined type mappings.

This class is immutable. This avoids threading issues, since an instance is often accessed by multiple threads. Any user custom provider services should also be immutable for the same reason.

Inheritance

Object

AdbTypeMapper

AdbMySqlClientTypeMapper

AdbMySqlConnectorTypeMapper

AdbNpgsqlTypeMapper

AdbOdbcTypeMapper

AdbSqlClientTypeMapper

AdbSQLiteTypeMapper

Implements

IAdbTypeMapper

Namespace: actionETL.Adb

Assembly: actionETL.dll

Syntax

public class AdbTypeMapper : IAdbTypeMapper

Constructors

AdbTypeMapper()

Initializes a new instance of the AdbTypeMapper class, which stores mappings between .NET types and database types, and allows setting the database type of database parameters from these mappings.

Declaration

protected AdbTypeMapper()

Fields

SetMappedTypeEnumMySqlTypePrefixes

Prefix strings where one must match DataTypeName for an on-the-fly enum to integer mapping to be made.

Declaration

protected static readonly string[] SetMappedTypeEnumMySqlTypePrefixes

Field Value

Type	Description
String[]

SetMappedTypeEnumSqlClientTypePrefixes

Prefix strings where one must match DataTypeName for an on-the-fly enum to integer mapping to be made.

Declaration

protected static readonly string[] SetMappedTypeEnumSqlClientTypePrefixes

Field Value

Type	Description
String[]

Methods

AddOrUpdateDbType(String, DbType)

Adds or updates a provider-independent DbType database type mapping.

Declaration

protected void AddOrUpdateDbType(string dotNetTypeName, DbType dbType)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
DbType	dbType	DbType enumeration value to map to.

Exceptions

Type	Condition
ArgumentException	dbType - Not a valid DbType. dotNetTypeName - Must supply a non-empty value.

AddOrUpdateDbType(String, DbType, Byte, Byte)

Adds or updates a provider-independent DbType database type mapping.

Declaration

protected void AddOrUpdateDbType(string dotNetTypeName, DbType dbType, byte precision, byte scale)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
DbType	dbType	DbType enumeration value to map to.
Byte	precision	The precision of the mapped database type.
Byte	scale	The scale of the mapped database type.

Exceptions

Type	Condition
ArgumentException	dbType - Not a valid DbType. dotNetTypeName - Must supply a non-empty value.

AddOrUpdateDbType(String, DbType, Int32)

Adds or updates a provider-independent DbType database type mapping.

Declaration

protected void AddOrUpdateDbType(string dotNetTypeName, DbType dbType, int size)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
DbType	dbType	DbType enumeration value to map to.
Int32	size	The size of the mapped database type.

Exceptions

Type	Condition
ArgumentException	dbType - Not a valid DbType. dotNetTypeName - Must supply a non-empty value.

AddOrUpdateDbTypeWithNullable(String, DbType)

Adds or updates a mapping from both the specified .Net type (e.g. "System.Int32") and a nullable version of the same type (i.e. "System.Int32?") to a provider-independent DbType database type (e.g. DbType.Int32).

Note that this is just a helper method, a nullable type mapping can be added on its own by using another method.

Declaration

protected void AddOrUpdateDbTypeWithNullable(string dotNetTypeName, DbType dbType)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
DbType	dbType	DbType enumeration value to map to.

Exceptions

Type	Condition
ArgumentException	dbType - Not a valid DbType. dotNetTypeName - Must supply a non-empty value.

AddOrUpdateFunc(String, Func<AdbParameter, Type, AdbColumnSchema, ParameterDirection, Boolean>)

Adds or updates a database type mapping function, that will be called every time a mapping is needed. Note that workers normally use this once, not per row.

Declaration

protected void AddOrUpdateFunc(string dotNetTypeName, Func<AdbParameter, Type, AdbColumnSchema, ParameterDirection, bool> setParameterTypeFunc)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
Func<AdbParameter, Type, AdbColumnSchema, ParameterDirection, Boolean>	setParameterTypeFunc	The parameter type mapping function. It must return true if the mapped type is a provider-specific type, false if the mapped type is a DbType, and null if no mapping was found.

Exceptions

Type	Condition
ArgumentNullException	setParameterTypeFunc
ArgumentException	dotNetTypeName - Must supply a non-empty value.

AddOrUpdateProviderType(String, Object)

Adds or updates a provider-specific database type mapping.

Declaration

protected void AddOrUpdateProviderType(string dotNetTypeName, object providerTypeEnum)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
Object	providerTypeEnum	Provider-specific enumeration value to map to, e.g. SqlDbType.UniqueIdentifier.

Exceptions

Type	Condition
ArgumentException	dotNetTypeName - Must supply a non-empty value.

AddOrUpdateProviderType(String, Object, Byte, Byte)

Adds or updates a provider-specific database type mapping.

Declaration

protected void AddOrUpdateProviderType(string dotNetTypeName, object providerTypeEnum, byte precision, byte scale)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
Object	providerTypeEnum	Provider-specific enumeration value to map to, e.g. SqlDbType.UniqueIdentifier.
Byte	precision	The precision of the mapped database type.
Byte	scale	The scale of the mapped database type.

Exceptions

Type	Condition
ArgumentException	dotNetTypeName - Must supply a non-empty value.

AddOrUpdateProviderType(String, Object, Int32)

Adds or updates a provider-specific database type mapping.

Declaration

protected void AddOrUpdateProviderType(string dotNetTypeName, object providerTypeEnum, int size)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.
Object	providerTypeEnum	Provider-specific enumeration value to map to, e.g. SqlDbType.UniqueIdentifier.
Int32	size	The size of the mapped database type.

Exceptions

Type	Condition
ArgumentException	dotNetTypeName - Must supply a non-empty value.

AddOrUpdateUntyped(String)

Adds or updates a mapping to untyped, i.e. to not set a type but still report a mapping was found. The database provider will deduce the database type at runtime for each value, e.g. for each row.

Note that allowing the provider to deduce the type is both error prone and can result in lower performance, so it is recommended to only use mappings that set the type explicitly, or use a Runtime mapping (which has access to more information than the provider), if at all possible.

Declaration

protected void AddOrUpdateUntyped(string dotNetTypeName)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.

Exceptions

Type	Condition
ArgumentException	dotNetTypeName - Must supply a non-empty value.

IsMapped(String)

Determines whether the specified .NET CLR type name is mapped.

Declaration

protected bool IsMapped(string dotNetTypeName)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.

Returns

Type	Description
Boolean	true if the specified .NET CLR type name is mapped; otherwise, false.

Exceptions

Type	Condition
ArgumentException	dotNetTypeName - Must supply a non-empty value.

Remove(String)

Removes the specified .NET CLR type mapping.

Declaration

protected bool Remove(string dotNetTypeName)

Parameters

Type	Name	Description
String	dotNetTypeName	Name of the .NET CLR type, e.g. "System.Int32". Must not be empty.

Returns

Type	Description
Boolean	true if the mapping was found and removed, otherwise false.

Exceptions

Type	Condition
ArgumentException	dotNetTypeName - Must supply a non-empty value.

SetMappedType(AdbParameter, Type, AdbColumnSchema, ParameterDirection)

Set the database type of a database parameter, using previously defined mappings. Override and call this method to add type processing before or after this type lookup is performed.

The database type can be provider-independent such as System.Data.DbType Int32, or a provider-specific one such as System.Data.SqlDbType UniqueIdentifier, or Untyped, which means the provider deduces the database type for each value, e.g. for each row.

Declaration

public virtual bool SetMappedType(AdbParameter adbParameter, Type dotNetType, AdbColumnSchema adbColumnSchema, ParameterDirection direction)

Parameters

Type	Name	Description
AdbParameter	adbParameter	The database parameter. Must not be null.
Type	dotNetType	The .NET CLR type (string, SqlDateTime, etc.) Must not be null.
AdbColumnSchema	adbColumnSchema	The schema for the database column, or null if not available.
ParameterDirection	direction	The parameter direction.

Returns

Type	Description
Boolean	true if a mapping was found (including Untyped), otherwise false.

Exceptions

Type	Condition
ArgumentException	providerTypeEnum is not of the correct provider type. The property is not set to a valid DbType.
ArgumentNullException	adbColumnSchema adbParameter dotNetType

SetMappedTypeForEnum(AdbParameter, Type, AdbColumnSchema, ParameterDirection, IEnumerable<String>)

Internal method to set the database type of a database parameter, using previously defined mappings.

The database type can be provider-independent such as System.Data.DbType Int32, or a provider-specific one such as System.Data.SqlDbType UniqueIdentifier, or Untyped, which means the provider deduces the database type for each value, e.g. for each row.

If no pre-defined mapping is found, and dotNetType is an enum or nullable enum, and adbColumnSchema is either null or an integral type, then the parameter is mapped to the enum underlying type. This allows the enum to be stored in an integer column.

Declaration

protected bool SetMappedTypeForEnum(AdbParameter adbParameter, Type dotNetType, AdbColumnSchema adbColumnSchema, ParameterDirection direction, IEnumerable<string> sqlTypePrefixes)

Parameters

Type	Name	Description
AdbParameter	adbParameter	The database parameter. Must not be null.
Type	dotNetType	The .NET CLR type (string, SqlDateTime, etc.) Must not be null.
AdbColumnSchema	adbColumnSchema	The schema for the database column, or null if not available.
ParameterDirection	direction	The parameter direction.
IEnumerable<String>	sqlTypePrefixes	An on-the-fly mapping from an enum to an integer is only attempted if either adbColumnSchema.DataTypeName has no value, or it has a value and one of the sqlTypePrefixes string matches the start of adbColumnSchema.DataTypeName.

Returns

Type	Description
Boolean	true if a mapping was found (including Untyped), otherwise false.

Exceptions

Type	Condition
ArgumentException	providerTypeEnum is not of the correct provider type. The property is not set to a valid DbType.
ArgumentNullException	adbColumnSchema adbParameter dotNetType

ToString()

Returns a String that represents this instance.

Declaration

public override string ToString()

Returns

Type	Description
String

Overrides

Object.ToString()

Implements

IAdbTypeMapper

See Also

IAdbTypeMapper