Class AdbGenericDataSourceInformationService

Base class that provides information about a data source behind a connection, such as what character to use for quoting, how to specify parameter markers etc. The information is mainly taken from the "DataSourceInformation" schema collection, and is used to write provider-independent database code.

This class can be used directly (if the settings works with your data source) when creating AdbProvider instances, use Get() to retrieve the required delegate. It supports positional parameters, and named parameters using @ or :. Commonly, this class is inherited by provider-specific classes, which typically overwrites some values.

Also see Information and AdbProvider.

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

AdbGenericDataSourceInformationService

AdbMySqlClientDataSourceInformationService

AdbMySqlConnectorDataSourceInformationService

AdbNpgsqlDataSourceInformationService

AdbOdbcDataSourceInformationService

AdbSqlClientDataSourceInformationService

AdbSQLiteDataSourceInformationService

Implements

IAdbDataSourceInformationService

Namespace: actionETL.Adb

Assembly: actionETL.dll

Syntax

public class AdbGenericDataSourceInformationService : IAdbDataSourceInformationService

Constructors

AdbGenericDataSourceInformationService(IAdbConnection)

Initializes a new instance of the AdbGenericDataSourceInformationService class, which provides information about a data source behind a connection, such as what character to use for quoting, how to specify parameter markers etc. This supports writing provider-independent database code. It supports positional parameters, and named parameters using @ or :.

The connection is opened if needed, and is closed before returning if (and only if) it was closed before the call.

Declaration

protected AdbGenericDataSourceInformationService(IAdbConnection adbConnection)

Parameters

Type	Name	Description
IAdbConnection	adbConnection	An Adb database connection.

Exceptions

Type	Condition
ArgumentNullException	adbConnection
Exception	(See the provider documentation for specific Open() exceptions.)
InvalidOperationException	May throw if the connection is associated with a transaction (this is provider dependent).

Properties

CompositeIdentifierSeparator

Gets or sets the primary composite identifier separator, that e.g. separates the table name from the schema name.

Note that some providers use a different character when including e.g. the database name. Therefore always use the methods in AdbTableInformation to manipulate table identifiers, such as ComposeTableIdentifierParts(String, String, String) and CreateTableIdentifier(String).

Declaration

public string CompositeIdentifierSeparator { get; protected set; }

Property Value

Type	Description
String

CompositeIdentifierSeparatorPattern

Gets the composite identifier separator regular expression pattern.

Declaration

public string CompositeIdentifierSeparatorPattern { get; protected set; }

Property Value

Type	Description
String

Connection

Gets the Adb database connection.

Declaration

public IAdbConnection Connection { get; }

Property Value

Type	Description
IAdbConnection

DataSourceProductName

Gets the name of the data source product.

Declaration

public string DataSourceProductName { get; protected set; }

Property Value

Type	Description
String

DataSourceProductVersion

Gets the data source product version.

Declaration

public string DataSourceProductVersion { get; protected set; }

Property Value

Type	Description
String

DataSourceProductVersionNormalized

Gets the normalized data source product version, which is easier (vs. DataSourceProductVersion) to compare to find out which version is greater.

Declaration

public string DataSourceProductVersionNormalized { get; protected set; }

Property Value

Type	Description
String

GroupByBehavior

Gets the relationship between the columns in a GROUP BY clause and the non-aggregated columns in the select-list of a SELECT statement.

Declaration

public GroupByBehavior GroupByBehavior { get; protected set; }

Property Value

Type	Description
GroupByBehavior

IdentifierCase

Gets how identifiers are treated by the data source when searching the system catalog.

Declaration

public IdentifierCase IdentifierCase { get; protected set; }

Property Value

Type	Description
IdentifierCase

IdentifierPattern

Gets the regular expression pattern that matches an unquoted (non-composite) identifier and has a match value of the identifier, or the empty string if not available.

Declaration

public string IdentifierPattern { get; protected set; }

Property Value

Type	Description
String	For example [A-Za-z0-9_#$].

IdentifierQuotePrefix

Gets or sets the identifier quote prefix, i.e. the quote string used on the left side of an identifier part.

Declaration

public string IdentifierQuotePrefix { get; protected set; }

Property Value

Type	Description
String

IdentifierQuotePrefixes

Gets or sets the identifier quote prefixes, i.e. all possible quote characters used on the left side of an identifier part.

Declaration

public string IdentifierQuotePrefixes { get; protected set; }

Property Value

Type	Description
String

IdentifierQuoteSuffix

Gets or sets the identifier quote suffix, i.e. the quote string used on the right side of an identifier part.

Declaration

public string IdentifierQuoteSuffix { get; protected set; }

Property Value

Type	Description
String

IdentifierQuoteSuffixes

Gets or sets the identifier quote suffixes, i.e. all possible quote characters used on the right side of an identifier part.

Declaration

public string IdentifierQuoteSuffixes { get; protected set; }

Property Value

Type	Description
String

OrderByColumnsInSelect

Gets whether columns in an ORDER BY clause must be in the select list.

Declaration

public bool OrderByColumnsInSelect { get; protected set; }

Property Value

Type	Description
Boolean	true if they are required to be in the select list, otherwise false.

ParameterMarker

Gets or sets the query parameter marker (i.e. placeholder), e.g. ?, @ or :.

Declaration

protected string ParameterMarker { get; set; }

Property Value

Type	Description
String

ParameterMarkerFormat

Gets a format string that can be used to format a parameter.

If named parameters are not supported, and the provider expects the use of the ? character, the format string should be ?, which would ignore the parameter name.

Declaration

public string ParameterMarkerFormat { get; protected set; }

Property Value

Type	Description
String	For example :{0} if named parameters are prefixed with a colon. If the names already include the prefix, this string would be {0}.

ParameterMarkerPattern

Gets a regular expression pattern that matches a parameter marker, and with a match value of the parameter name, if any.

Declaration

public string ParameterMarkerPattern { get; protected set; }

Property Value

Type	Description
String	The regular expression parameter marker pattern. For example, if named parameters are supported with an @ prefix that is included in the parameter name, this could be: (@[A-Za-z0-9_$#]*). If named parameters instead are supported with a : prefix and it is not part of the parameter name, this could be: :([A-Za-z0-9_$#]*). If named parameters are not supported, this would be ?.

ParameterNameMaxLength

Gets the maximum length in characters of the parameter name, or 0 if parameter names are not supported.

Declaration

public int ParameterNameMaxLength { get; protected set; }

Property Value

Type	Description
Int32

ParameterNamePattern

Gets the regular expression pattern that matches valid parameter names.

Declaration

public string ParameterNamePattern { get; protected set; }

Property Value

Type	Description
String

QuotedIdentifierCase

Gets whether quoted identifiers are treated as case sensitive or not.

Declaration

public IdentifierCase QuotedIdentifierCase { get; protected set; }

Property Value

Type	Description
IdentifierCase

QuotedIdentifierPattern

Gets a regular expression that matches a quoted (non-composite) identifier and has a match value of the identifier itself without the quotes.

Declaration

public string QuotedIdentifierPattern { get; protected set; }

Property Value

Type	Description
String	The quoted identifier regular expression pattern. For example, if the data source uses double-quotes to identify quoted identifiers, this would be: (([^\"]|\"\")*).

StatementSeparatorPattern

Gets a regular expression pattern that matches the statement separator.

Declaration

public string StatementSeparatorPattern { get; protected set; }

Property Value

Type	Description
String

StringLiteralPattern

Gets a regular expression pattern that matches a string literal, and has a match value of the literal itself.

Declaration

public string StringLiteralPattern { get; protected set; }

Property Value

Type	Description
String	For example, if the data source uses single-quotes to identify strings, this would be: ('([^']|'')*')

SupportedJoinOperators

Gets the supported join operators.

Declaration

public SupportedJoinOperators SupportedJoinOperators { get; }

Property Value

Type	Description
SupportedJoinOperators

UsesPositionalParameters

Gets or sets whether the provider uses positional (true) or named (false) parameters. Defaults to true if ParameterMarkerFormat equals "?"; otherwise false. Also see GetPlaceholder(String).

Declaration

public bool UsesPositionalParameters { get; protected set; }

Property Value

Type	Description
Boolean

Methods

Get()

Gets a function that returns a new instance of AdbGenericDataSourceInformationService (with default settings) on each invocation, which is used when instantiating a new AdbProvider.

Declaration

public static Func<IAdbConnection, IAdbDataSourceInformationService> Get()

Returns

Type	Description
Func<IAdbConnection, IAdbDataSourceInformationService>

GetPlaceholder(String)

Returns the parameter placeholder string, for creating SQL queries. Only supports ? for positional parameters, as well as @ (e.g. @MyName) and : (e.g. :MyName for prefix named parameters. Override this method if this is not correct.

Declaration

public virtual string GetPlaceholder(string parameterName)

Parameters

Type	Name	Description
String	parameterName	The parameter name, with or without a parameter marker.

Returns

Type	Description
String	The parameter placeholder, ? for positional parameters, or e.g. @MyName or :MyName for named parameters.

Exceptions

Type	Condition
ArgumentException	parameterName - Must not be empty.

QuoteIdentifierPart(String)

Quotes the table or column identifier part, i.e. column name, table name, schema/owner name, or database/catalog name. Does not quote it if it's already quoted with IdentifierQuotePrefix and IdentifierQuoteSuffix.

Declaration

public virtual string QuoteIdentifierPart(string unquotedIdentifierPart)

Parameters

Type	Name	Description
String	unquotedIdentifierPart	The potentially unquoted identifier part.

Returns

Type	Description
String	The quoted identifier part. null if unquotedIdentifierPart is null. An empty string if unquotedIdentifierPart is an empty string.

StripParameterMarker(String)

Returns the specified parameter name with a parameter marker removed (if present), if the provider uses named parameters. Otherwise the parameter name is returned unchanged.

Supports named parameters that uses @ and : prefixes, override the method if this is not sufficient.

Declaration

public virtual string StripParameterMarker(string parameterName)

Parameters

Type	Name	Description
String	parameterName	The parameter name, with or without a parameter marker.

Returns

Type	Description
String	The parameter name, with any parameter marker removed.

Exceptions

Type	Condition
ArgumentNullException	parameterName

ToString()

Returns a string that represents this instance.

Declaration

public override string ToString()

Returns

Type	Description
String

Overrides

Object.ToString()

Implements

IAdbDataSourceInformationService

See Also

Information