TDAJoinDataTable
Overview
The TDAJoinDataTable class represents a special data table that joins data from several tables. This data table acts similarly to the JOIN
operator used in SQL.
In Data Abstract, the TDAJoinDataTable is used internally by the Quey Builder to generate proper SQL JOIN
statements for SELECT
queries.
Location
- Unit: uDAJoinDataTables.pas
- Ancestry: TCollectionItem | TDASQLCommand | TDADataset | TDAJoinDataTable
constructor Create override
Creates a new instance.
constructor Create(Collection: TCollection)
Parameters:
- Collection: owner collection.
Assign override
Copies data from a given source.
procedure Assign(aSource: TPersistent)
Parameters:
- aSource: Instance whose properties will be copied
BusinessClassID (declared in TDADataset)
The property is used for implementing business rules logic on a dataset level.
property BusinessClassID: string read write
BusinessRulesClient (declared in TDASQLCommand)
Business rule script (client-side)
property BusinessRulesClient: TDAClientBusinessRuleScript read write
BusinessRulesServer (declared in TDASQLCommand)
Business rule script (server-side)
property BusinessRulesServer: TDABusinessRuleScript read write
CustomAttributes (declared in TDASQLCommand)
Custom attributes of the sql command.
property CustomAttributes: TStrings read write
DeleteCommandName (declared in TDADataset)
This command will be used to apply DELETE changes for the data table back to the server. This property only needs to be assigned if your schema provides a special command for processing DELETE changes (which could be an SQL DELETE statement or a stored procedure).
property DeleteCommandName: string read write
Description (declared in TDASQLCommand)
Describes the command. This property will not be used by the Data Abstract library, but can be filled with description text for documentation purposes when defining the command in Schema Modeler.
property Description: string read write
DynamicWhereExpression (declared in TDASQLCommand)
property DynamicWhereExpression: TDAWhereExpression read write
DynamicWhereXML (declared in TDASQLCommand)
Dynamic Where xml
property DynamicWhereXML: UnicodeString read write
FieldByName (declared in TDADataset)
Finds a field based on its name. If the specified field does not exist, FieldByName raises an exception.
function FieldByName(const aName: string): TDAField
Parameters:
- aName: name of the searched field
Fields (declared in TDADataset)
Provides access to all the fields contained in the dataset.
property Fields: TDAFieldCollection read write
FindField (declared in TDADataset)
Returns an item with the specified name.
function FindField(const aName: string): TDAField
Parameters:
- aName: name of the searched field
GetDisplayName protected override (declared in TDASQLCommand)
Returns the name of the sql command as it appears in the collection editor.
function GetDisplayName: string
GetFieldCollectionClass protected virtual (declared in TDADataset)
Returns TDAFieldCollection class
function GetFieldCollectionClass: TDAFieldCollectionClass
GetSQLCommandCollection protected override
Returns the SQL commands collection. Not supported for this class.
function GetSQLCommandCollection: TDASQLCommandCollection
InsertCommandName (declared in TDADataset)
This command will be used to apply INSERT changes for the data table back to the server. This property only needs to be assigned if your schema provides a special command for processing INSERT changes (which could be an SQL INSERT statement or a stored procedure).
property InsertCommandName: string read write
IsPublic (declared in TDASQLCommand)
Accessible from client-side or not.
property IsPublic: Boolean read write
JoinSourceTables
References to the collection of source tables (TDAJoinSourceTable items) in the specified JOIN
statements.
property JoinSourceTables: TDAJoinSourceTableCollection read write
MasterTable
Holds the name of the master table.
property MasterTable: string read write
Name (declared in TDASQLCommand)
Sets the name that uniquely identifies this command. This name can be the name of the underlying stored procedure, or any human-readable name that describes the purpose of the command.
property Name: string read write
ParamByName (declared in TDASQLCommand)
Locates a specific parameter defined for the command, based on its name. If no matching parameter is defined, an exception will be raised.
function ParamByName(const aName: string): TDAParam
Parameters:
- aName: name of the parameter
Params
Provides access to the parameters collection of the join data table. Not supported for this class.
property Params: TDAParamCollection read write
ReadOnly (declared in TDADataset)
Manages whether the data table is read-only (true) or not (false, default). If enabled, no changes to the data contained in the table will be permitted.
property ReadOnly: Boolean read write
SetDisplayName protected override (declared in TDASQLCommand)
Sets the name of the command as it appears in the collection editor.
procedure SetDisplayName(const Value: string)
Parameters:
- Value: value for the Name property
SQLCommandCollection (declared in TDASQLCommand)
References the collection that this command belongs to. Usually, this will be the Commands property of the TDASchema that this command is defined in.
property SQLCommandCollection: TDASQLCommandCollection read
Statements
Provides access to the statements collection of the joined data table. Not supported for this class.
property Statements: TDAStatementCollection read write
UpdateCommandName (declared in TDADataset)
This command will be used to apply UPDATE changes for the data table back to the server. This property only needs to be assigned if your schema provides a special command for processing UPDATE changes (which could be an SQL UPDATE statement or a stored procedure).
property UpdateCommandName: string read write
BusinessClassID (declared in TDADataset)
The property is used for implementing business rules logic on a dataset level.
property BusinessClassID: string read write
BusinessRulesClient (declared in TDASQLCommand)
Business rule script (client-side)
property BusinessRulesClient: TDAClientBusinessRuleScript read write
BusinessRulesServer (declared in TDASQLCommand)
Business rule script (server-side)
property BusinessRulesServer: TDABusinessRuleScript read write
CustomAttributes (declared in TDASQLCommand)
Custom attributes of the sql command.
property CustomAttributes: TStrings read write
DeleteCommandName (declared in TDADataset)
This command will be used to apply DELETE changes for the data table back to the server. This property only needs to be assigned if your schema provides a special command for processing DELETE changes (which could be an SQL DELETE statement or a stored procedure).
property DeleteCommandName: string read write
Description (declared in TDASQLCommand)
Describes the command. This property will not be used by the Data Abstract library, but can be filled with description text for documentation purposes when defining the command in Schema Modeler.
property Description: string read write
DynamicWhereExpression (declared in TDASQLCommand)
property DynamicWhereExpression: TDAWhereExpression read write
DynamicWhereXML (declared in TDASQLCommand)
Dynamic Where xml
property DynamicWhereXML: UnicodeString read write
Fields (declared in TDADataset)
Provides access to all the fields contained in the dataset.
property Fields: TDAFieldCollection read write
InsertCommandName (declared in TDADataset)
This command will be used to apply INSERT changes for the data table back to the server. This property only needs to be assigned if your schema provides a special command for processing INSERT changes (which could be an SQL INSERT statement or a stored procedure).
property InsertCommandName: string read write
IsPublic (declared in TDASQLCommand)
Accessible from client-side or not.
property IsPublic: Boolean read write
JoinSourceTables
References to the collection of source tables (TDAJoinSourceTable items) in the specified JOIN
statements.
property JoinSourceTables: TDAJoinSourceTableCollection read write
MasterTable
Holds the name of the master table.
property MasterTable: string read write
Name (declared in TDASQLCommand)
Sets the name that uniquely identifies this command. This name can be the name of the underlying stored procedure, or any human-readable name that describes the purpose of the command.
property Name: string read write
Params
Provides access to the parameters collection of the join data table. Not supported for this class.
property Params: TDAParamCollection read write
ReadOnly (declared in TDADataset)
Manages whether the data table is read-only (true) or not (false, default). If enabled, no changes to the data contained in the table will be permitted.
property ReadOnly: Boolean read write
SQLCommandCollection (declared in TDASQLCommand)
References the collection that this command belongs to. Usually, this will be the Commands property of the TDASchema that this command is defined in.
property SQLCommandCollection: TDASQLCommandCollection read
Statements
Provides access to the statements collection of the joined data table. Not supported for this class.
property Statements: TDAStatementCollection read write
UpdateCommandName (declared in TDADataset)
This command will be used to apply UPDATE changes for the data table back to the server. This property only needs to be assigned if your schema provides a special command for processing UPDATE changes (which could be an SQL UPDATE statement or a stored procedure).
property UpdateCommandName: string read write
constructor Create override
Creates a new instance.
constructor Create(Collection: TCollection)
Parameters:
- Collection: owner collection.
Assign override
Copies data from a given source.
procedure Assign(aSource: TPersistent)
Parameters:
- aSource: Instance whose properties will be copied
FieldByName (declared in TDADataset)
Finds a field based on its name. If the specified field does not exist, FieldByName raises an exception.
function FieldByName(const aName: string): TDAField
Parameters:
- aName: name of the searched field
FindField (declared in TDADataset)
Returns an item with the specified name.
function FindField(const aName: string): TDAField
Parameters:
- aName: name of the searched field
GetDisplayName protected override (declared in TDASQLCommand)
Returns the name of the sql command as it appears in the collection editor.
function GetDisplayName: string
GetFieldCollectionClass protected virtual (declared in TDADataset)
Returns TDAFieldCollection class
function GetFieldCollectionClass: TDAFieldCollectionClass
GetSQLCommandCollection protected override
Returns the SQL commands collection. Not supported for this class.
function GetSQLCommandCollection: TDASQLCommandCollection
ParamByName (declared in TDASQLCommand)
Locates a specific parameter defined for the command, based on its name. If no matching parameter is defined, an exception will be raised.
function ParamByName(const aName: string): TDAParam
Parameters:
- aName: name of the parameter
SetDisplayName protected override (declared in TDASQLCommand)
Sets the name of the command as it appears in the collection editor.
procedure SetDisplayName(const Value: string)
Parameters:
- Value: value for the Name property