InstantTypes

Unit: InstantTypesCategory: Core

Overview

The InstantTypes unit defines all fundamental types, enumerations, and constants used throughout InstantObjects. These definitions provide type safety, consistency, and cross-platform compatibility across the framework.

Key Contents:

Attribute Types - Types of object attributes (String, Integer, Reference, etc.)
Data Types - Database field types
Storage Kinds - How attributes are stored (Embedded, External, Virtual)
Operation Types - CRUD operation identifiers
Conflict Actions - Concurrency resolution strategies
Load Modes - Query result loading strategies
SQL Engines - Supported database engines
Platform Types - 64-bit compatibility types

Type Definitions

Platform-Specific Types

pascal

{$IF DEFINED(WINLINUX64) OR DEFINED(USE_LARGEINT_FIELD_FOR_REF)}
IORefFieldType = ftLargeInt;
{$ELSE}
IORefFieldType = ftInteger;
{$IFEND}

Platform-specific field type for object references. Uses ftLargeInt on 64-bit platforms for extended range.

pascal

TListSize = NativeInt;  // Delphi 11+
TListSize = Integer;    // Earlier versions

List index and count type, sized appropriately for platform.

pascal

TIORefValueType = {$IFDEF WINLINUX64}NativeInt{$ELSE}Integer{$ENDIF};

Reference value type, matches platform pointer size.

Enumerations

TInstantAttributeType

Defines the type of an attribute in a business object.

pascal

type
  TInstantAttributeType = (
    atUnknown,      // Not set or undefined
    atInteger,      // Integer value
    atFloat,        // Floating point value
    atCurrency,     // Currency value (fixed decimal)
    atBoolean,      // Boolean value
    atString,       // String value
    atDateTime,     // Date and time combined
    atBlob,         // Binary large object
    atMemo,         // Text memo (large text)
    atGraphic,      // Image or graphic
    atPart,         // Single owned object (composition)
    atReference,    // Single referenced object (association)
    atParts,        // Collection of owned objects
    atReferences,   // Collection of referenced objects
    atDate,         // Date only
    atTime,         // Time only
    atEnum,         // Enumeration value
    atTimeStamp     // Date and time with the highest precision of the database (4.4.0)
  );

New in 4.4.0: TimeStamp

atTimeStamp (class TInstantTimeStamp, data type dtTimeStamp) stores date and time with the highest precision supported by the database. In the IOMETADATA it is declared as Name: TimeStamp; and its property is a TDateTime. On the Delphi side the precision is the millisecond (TDateTime); the column type keeps the values written with a higher precision by the database itself.

Categories:

Category	Types	Description
Simple	Integer, Float, Currency, Boolean, String, DateTime, Date, Time, TimeStamp, Enum	Value types
Complex	Blob, Memo, Graphic	Large object types
Container	Part, Parts, Reference, References	Relational types

Usage:

pascal

var
  Attr: TInstantAttributeMetadata;
begin
  Attr := ClassMeta.AttributeMetadatas.Add;
  Attr.Name := 'Email';
  Attr.AttributeType := atString;  // Simple value type
  Attr.Size := 100;
end;

Attr := ClassMeta.AttributeMetadatas.Add;
Attr.Name := 'Category';
Attr.AttributeType := atReference;  // Association
Attr.ObjectClassName := 'TCategory';

Attr := ClassMeta.AttributeMetadatas.Add;
Attr.Name := 'Phones';
Attr.AttributeType := atParts;  // Composition collection
Attr.ObjectClassName := 'TPhone';

TInstantAttributeCategory

Categorizes attribute types into broad groups.

pascal

type
  TInstantAttributeCategory = (
    acUnknown,     // Not categorized
    acSimple,      // Simple value types
    acElement,     // Complex types (Blob, Memo, Graphic)
    acContainer    // Relational types (Part, Parts, Reference, References)
  );

Mapping:

pascal

function GetAttributeCategory(AttrType: TInstantAttributeType): TInstantAttributeCategory;
begin
  case AttrType of
    atInteger, atFloat, atCurrency, atBoolean, atString,
    atDateTime, atDate, atTime, atTimeStamp, atEnum:
      Result := acSimple;
    atBlob, atMemo, atGraphic:
      Result := acElement;
    atPart, atParts, atReference, atReferences:
      Result := acContainer;
  else
    Result := acUnknown;
  end;
end;

TInstantDataType

Defines database field data types.

pascal

type
  TInstantDataType = (
    dtInteger,     // Integer field
    dtFloat,       // Floating point field
    dtCurrency,    // Currency/decimal field
    dtBoolean,     // Boolean/bit field
    dtString,      // String/varchar field
    dtMemo,        // Memo/text field
    dtDateTime,    // DateTime field (milliseconds precision where available)
    dtBlob,        // Binary blob field
    dtDate,        // Date field
    dtTime,        // Time field
    dtEnum,        // Enumeration (stored as integer)
    dtTimeStamp    // Date and time with the highest precision of the database (4.4.0)
  );

  TInstantDataTypes = set of TInstantDataType;

Mappings of the FireDAC broker (database-dependent):

TInstantDataType	SQL Server	PostgreSQL	Firebird/InterBase	MySQL	Oracle	SQLite
dtInteger	INTEGER	INTEGER	INTEGER	INTEGER	NUMBER(10,0)	INTEGER
dtFloat	FLOAT	FLOAT8	DOUBLE PRECISION	FLOAT	NUMBER(28,15)	FLOAT
dtCurrency	MONEY	DECIMAL(18,4)	DECIMAL(18,4)	DECIMAL(18,4)	NUMBER(18,4)	NUMERIC(18,4)
dtBoolean	BIT	BOOLEAN	SMALLINT	TINYINT(1)	NUMBER(1,0)	BOOLEAN
dtString	VARCHAR(n)	VARCHAR(n)	VARCHAR(n)	VARCHAR(n)	VARCHAR2(n)	VARCHAR(n)
dtMemo	TEXT	TEXT	BLOB SUB_TYPE 1	TEXT	CLOB	TEXT
dtDateTime	DATETIME2(3)	TIMESTAMP	TIMESTAMP	DATETIME	DATE	TIMESTAMP
dtDate	DATETIME	TIMESTAMP	TIMESTAMP	DATE	DATE	TIMESTAMP
dtTime	DATETIME	TIMESTAMP	TIMESTAMP	TIME	DATE	TIMESTAMP
dtTimeStamp	DATETIME2(7)	TIMESTAMP(6)	TIMESTAMP	DATETIME(6)	TIMESTAMP(6)	TIMESTAMP
dtBlob	IMAGE	BYTEA	BLOB	BLOB	BLOB	BLOB
dtEnum	INTEGER	INTEGER	INTEGER	INTEGER	NUMBER(10,0)	INTEGER

DATETIME2 only with FireDAC

DATETIME2(3) and DATETIME2(7) are used only by the FireDAC broker. The ADO and DBX brokers for MS SQL Server keep DATETIME for both DateTime and TimeStamp attributes, because legacy OLE DB providers (SQLOLEDB) read DATETIME2 columns as strings. The IBX broker uses TIMESTAMP for both.

Usage:

pascal

var
  Field: TInstantFieldMetadata;
begin
  Field := Table.FieldMetadatas.Add;
  Field.Name := 'Name';
  Field.DataType := dtString;
  Field.Size := 100;

  Field := Table.FieldMetadatas.Add;
  Field.Name := 'BirthDate';
  Field.DataType := dtDate;  // No size needed

  Field := Table.FieldMetadatas.Add;
  Field.Name := 'Balance';
  Field.DataType := dtCurrency;  // Fixed decimal
end;

TInstantStorageKind

Defines how an attribute is stored.

pascal

type
  TInstantStorageKind = (
    skEmbedded,     // Stored in class table (default)
    skExternal,     // Stored in separate table
    skVirtual,      // Not stored (transient/calculated)
    skForeignKeys   // Stored using foreign keys (advanced)
  );

Details:

Kind	Description	Use For	Example
skEmbedded	Field(s) in class table	Simple attributes, single references	Name, Email, CategoryId
skExternal	Separate link table	Parts/References collections	Contact.Phones → ContactPhones table
skVirtual	Not persisted	Calculated properties	FullName (FirstName + LastName)
skForeignKeys	Foreign key fields	Custom reference storage	Advanced scenarios

Example:

pascal

// Embedded reference (default)
Attr := ClassMeta.AttributeMetadatas.Add;
Attr.Name := 'Category';
Attr.AttributeType := atReference;
Attr.StorageKind := skEmbedded;  // CategoryClass, CategoryId in Contact table

// External collection
Attr := ClassMeta.AttributeMetadatas.Add;
Attr.Name := 'Phones';
Attr.AttributeType := atParts;
Attr.StorageKind := skExternal;  // Separate ContactPhones table
Attr.ExternalStorageName := 'ContactPhones';

// Virtual attribute
Attr := ClassMeta.AttributeMetadatas.Add;
Attr.Name := 'FullName';
Attr.AttributeType := atString;
Attr.StorageKind := skVirtual;  // Not stored, calculated at runtime

TInstantPersistence

Defines class persistence mode.

pascal

type
  TInstantPersistence = (
    peEmbedded,    // Stored as blob in parent object
    peStored       // Stored in its own table (default)
  );

Details:

Mode	Description	Use For	Storage
peStored	Normal persistence	Regular business classes	Separate table
peEmbedded	Embedded in parent	Small nested objects	Blob in parent

Example:

pascal

// Normal class
ClassMeta := Model.ClassMetadatas.Add;
ClassMeta.Name := 'TContact';
ClassMeta.Persistence := peStored;  // Own table: CONTACTS
ClassMeta.StorageName := 'CONTACTS';

// Embedded class
ClassMeta := Model.ClassMetadatas.Add;
ClassMeta.Name := 'TAddress';
ClassMeta.Persistence := peEmbedded;  // No separate table
// Stored as blob in parent objects

TInstantFieldOptions

Field-level options for database schema.

pascal

type
  TInstantFieldOption = (
    foRequired,      // NOT NULL constraint
    foIndexed,       // Create index on field
    foUnique,        // Unique constraint
    foPrimaryKey,    // Part of primary key
    foMultiLanguage  // Multi-language support
  );

  TInstantFieldOptions = set of TInstantFieldOption;

Usage:

pascal

// Required field
Table.FieldMetadatas.AddFieldMetadata('Name', dtString, 100, [foRequired]);

// Unique index
Table.FieldMetadatas.AddFieldMetadata('Email', dtString, 100, [foRequired, foUnique, foIndexed]);

// Primary key
Table.FieldMetadatas.AddFieldMetadata('Id', dtString, 32, [foRequired, foPrimaryKey]);

// Index only
Table.FieldMetadatas.AddFieldMetadata('CategoryId', dtString, 32, [foIndexed]);

TInstantOperationType

Type of persistence operation.

pascal

type
  TInstantOperationType = (
    otNone,        // No operation
    otCreate,      // Creating new object
    otStore,       // Storing object
    otRetrieve,    // Retrieving object
    otRefresh,     // Refreshing object
    otDispose      // Disposing object
  );

Used in:

Error handling events
Logging and auditing
Transaction management
Operation-specific logic

Example:

pascal

procedure TMainForm.ConnectorError(Sender: TObject;
  OperationType: TInstantOperationType; E: Exception;
  var Action: TInstantErrorAction);
begin
  case OperationType of
    otStore:
      begin
        LogError('Store failed: ' + E.Message);
        Action := eaRetry;  // Retry store operations
      end;
    otRetrieve:
      begin
        ShowMessage('Object not found: ' + E.Message);
        Action := eaIgnore;  // Ignore retrieve errors
      end;
  else
    Action := eaError;  // Fail on other errors
  end;
end;

TInstantErrorAction

Action to take on persistence error.

pascal

type
  TInstantErrorAction = (
    eaRetry,       // Retry the operation
    eaIgnore,      // Ignore the error and continue
    eaError,       // Raise exception (default)
    eaRevert,      // Revert changes
    eaCancel       // Cancel operation
  );

Used in: TInstantConnector.OnError event

TInstantConflictAction

Action on concurrency conflict.

pascal

type
  TInstantConflictAction = (
    caIgnore,      // Overwrite (no concurrency check)
    caFail         // Fail on conflict (default)
  );

Usage:

pascal

// Default: Fail on conflict (optimistic locking)
Contact.Store;  // or Contact.Store(caFail);

// Overwrite without checking
Contact.Store(caIgnore);  // Dangerous! May overwrite changes

// Refresh on conflict
try
  Contact.Store(caFail);
except
  on E: EInstantConflict do
  begin
    Contact.Refresh;  // Reload from database
    // Re-apply changes or notify user
  end;
end;

TInstantContentChangeType

Type of change in a container (Parts/References collection).

pascal

type
  TInstantContentChangeType = (
    ctAdd,         // Item added
    ctAddRef,      // Reference added (without ownership)
    ctRemove,      // Item removed
    ctReplace,     // Item replaced
    ctClear        // Container cleared
  );

Used in: TInstantObject.OnContentChange event

Example:

pascal

procedure TMainForm.ContactContentChange(Sender: TInstantObject;
  Container: TInstantContainer; ChangeType: TInstantContentChangeType;
  Index: Integer; AObject: TInstantObject);
begin
  case ChangeType of
    ctAdd:
      LogChange('Added ' + AObject.ClassName + ' at ' + IntToStr(Index));
    ctRemove:
      LogChange('Removed from ' + IntToStr(Index));
    ctClear:
      LogChange('Cleared ' + Container.Name);
  end;
end;

TInstantLoadMode

Query result loading strategy for SQL brokers.

pascal

type
  TInstantLoadMode = (
    lmKeysFirst,      // Load keys first, materialize on demand (default)
    lmPartialBurst,   // Load simple attributes first, rest on demand
    lmFullBurst       // Load everything upfront
  );

Details:

Mode	First Query	Materialization	Database Hits	Memory	Use For
lmKeysFirst	SELECT Id, Class	On access, full object	1 + N	Low	Large result sets
lmPartialBurst	SELECT Id, Class, simple attributes	On access, complex/container	1 + partial N	Medium	Moderate result sets
lmFullBurst	SELECT everything	Immediate, all objects	1	High	Small result sets, eager loading

Performance Comparison:

Query: SELECT * FROM TContact (1000 objects)

lmKeysFirst (default):
  Initial: SELECT Class, Id FROM Contacts          -- Fast, 1000 rows
  Per object access: SELECT * FROM Contacts WHERE Id = ?  -- 1000 queries
  Total queries: 1 + 1000 = 1001
  Memory: Low (only accessed objects loaded)

lmPartialBurst:
  Initial: SELECT Class, Id, Name, Email, ... FROM Contacts  -- Medium, 1000 rows
  Per complex/container: SELECT * FROM ContactPhones WHERE ContactId = ?
  Total queries: 1 + (containers accessed)
  Memory: Medium (simple data pre-loaded)

lmFullBurst:
  Initial: SELECT everything with JOINs     -- Slow, large result set
  Materialization: Immediate
  Total queries: 1
  Memory: High (all 1000 objects in memory)

Usage:

pascal

var
  Query: TInstantQuery;
begin
  Query := TInstantQuery.Create(nil);
  try
    Query.Connector := FireDACConnector;
    Query.Command := 'SELECT * FROM TContact';

    // Default: Keys first (good for large result sets)
    Query.RequestedLoadMode := lmKeysFirst;
    Query.Open;
    // Objects loaded on demand: for I := 0 to Query.ObjectCount - 1...

    // Partial burst (good for displaying list with simple properties)
    Query.RequestedLoadMode := lmPartialBurst;
    Query.Open;
    // Simple attributes pre-loaded, fast for grid display

    // Full burst (good for small result sets, need everything)
    Query.RequestedLoadMode := lmFullBurst;
    Query.Open;
    // All objects fully loaded immediately
  finally
    Query.Free;
  end;
end;

// Check actual mode (may fall back)
if Query.ActualLoadMode <> Query.RequestedLoadMode then
  ShowMessage('Load mode not supported, using: ' +
    GetEnumName(TypeInfo(TInstantLoadMode), Ord(Query.ActualLoadMode)));

Helper Function:

pascal

function IsBurstLoadMode(const ALoadMode: TInstantLoadMode): Boolean; inline;
begin
  Result := ALoadMode in [lmPartialBurst, lmFullBurst];
end;

TInstantSQLEngine

Identifies database engine for SQL dialect.

pascal

type
  TInstantSQLEngine = (
    seGenericSQL,   // Generic SQL (ANSI standard)
    seMSSQL,        // Microsoft SQL Server
    seOracle,       // Oracle Database
    seFirebird,     // Firebird
    seInterbase,    // InterBase
    seMySQL,        // MySQL / MariaDB
    sePostgres,     // PostgreSQL
    seSQLLite,      // SQLite
    seSybase        // Sybase
  );

Used for:

SQL dialect generation
NOLOCK hints (SQL Server)
Function translation
Date/time formatting
Reserved word handling

Example:

pascal

// Set SQL engine on connector
FireDACConnector.SQLEngine := seMSSQL;  // SQL Server

// Get NOLOCK directive
function GetTableNoLockDirective(AEngine: TInstantSQLEngine): string;
begin
  if AEngine = seMSSQL then
    Result := ' WITH(NOLOCK)'  // SQL Server
  else
    Result := '';  // Other databases
end;

// Usage in query
if FireDACConnector.ReadObjectListWithNoLock then
  SQL := 'SELECT * FROM Contacts' + GetTableNoLockDirective(FireDACConnector.SQLEngine);
// SQL Server: "SELECT * FROM Contacts WITH(NOLOCK)"
// Others:     "SELECT * FROM Contacts"

TInstantGraphicFileFormat

Image file format enumeration.

pascal

type
  TInstantGraphicFileFormat = (
    gffUnknown,    // Unknown or unsupported format
    gffBmp,        // Windows Bitmap
    gffTiff,       // Tagged Image File Format
    gffJpeg,       // JPEG
    gffPng,        // Portable Network Graphics
    gffDcx,        // Multi-page PCX
    gffPcx,        // PC Paintbrush
    gffEmf,        // Enhanced Metafile
    gffGif,        // Graphics Interchange Format
    gffIco         // Windows Icon
  );

Used in: TInstantGraphic attribute for image format detection and conversion.

TInstantCatalogFeature

Catalog capabilities for reading database metadata.

pascal

type
  TInstantCatalogFeature = (
    cfReadTableInfo,   // Can read table names
    cfReadColumnInfo,  // Can read column definitions
    cfReadIndexInfo    // Can read index definitions
  );

  TInstantCatalogFeatures = set of TInstantCatalogFeature;

Example:

pascal

var
  Catalog: TInstantCatalog;
  Features: TInstantCatalogFeatures;
begin
  Catalog := FireDACConnector.Broker.CreateCatalog(Scheme);
  Features := Catalog.Features;

  if cfReadTableInfo in Features then
    ShowMessage('Can read table names');

  if cfReadColumnInfo in Features then
    ShowMessage('Can read column definitions');

  if cfReadIndexInfo in Features then
    ShowMessage('Can read index definitions');

  // Typical SQL broker: all features supported
  // File-based broker (XML/JSON): features limited or none
end;

TInstantDBBuildCommandType

Type of database build command.

pascal

type
  TInstantDBBuildCommandType = (
    ctAddTable,      // CREATE TABLE
    ctDropTable,     // DROP TABLE
    ctAddField,      // ALTER TABLE ADD COLUMN
    ctAlterField,    // ALTER TABLE ALTER COLUMN
    ctDropField,     // ALTER TABLE DROP COLUMN
    ctAddIndex,      // CREATE INDEX
    ctAlterIndex,    // DROP INDEX + CREATE INDEX
    ctDropIndex      // DROP INDEX
  );

Used in: TInstantDBBuilder and TInstantDBEvolution for schema operations.

TInstantObjectNotification

Object lifecycle notification.

pascal

type
  TInstantObjectNotification = (
    onChanged,      // Object modified
    onCreated,      // Object created
    onDisposed,     // Object disposed
    onRefreshed,    // Object refreshed from database
    onRetrieved,    // Object retrieved from database
    onStored        // Object stored to database
  );

Used in: Object notification events and observer pattern.

Example:

pascal

procedure TMainForm.ObjectNotification(Sender: TInstantObject;
  Notification: TInstantObjectNotification);
begin
  case Notification of
    onCreated:
      LogEvent('Created: ' + Sender.Id);
    onStored:
      LogEvent('Stored: ' + Sender.Id);
    onDisposed:
      LogEvent('Disposed: ' + Sender.Id);
    onChanged:
      UpdateUI(Sender);
  end;
end;

TInstantVerificationResult

Result of user verification/confirmation.

pascal

type
  TInstantVerificationResult = (
    vrOk,          // Continue
    vrCancel,      // Cancel current operation
    vrAbort,       // Abort entire process
    vrError        // Error occurred
  );

Used in: Interactive database build/evolution for user confirmation.

TInstantCacheNodeColor

AVL tree node color (internal).

pascal

type
  TInstantCacheNodeColor = (
    ncRed,         // Red node
    ncBlack        // Black node
  );

Used in: Internal object cache balanced tree implementation.

Event Types

TInstantWarningEvent

Non-fatal warning during operations.

pascal

type
  TInstantWarningEvent = procedure(const Sender: TObject;
    const AWarningText: string) of object;

Used in:

TInstantScheme.OnWarning
TInstantCatalog.OnWarning
Database build/evolution warnings

Example:

pascal

procedure TMainForm.SchemeWarning(const Sender: TObject;
  const AWarningText: string);
begin
  Memo1.Lines.Add('WARNING: ' + AWarningText);
end;

Scheme.OnWarning := SchemeWarning;

Type Aliases

TInstantBytes

Byte array type.

pascal

type
  TInstantBytes = TBytes;

Standard dynamic byte array, used for binary data.

Helper Functions

IsBurstLoadMode

Checks if load mode is a burst mode.

pascal

function IsBurstLoadMode(const ALoadMode: TInstantLoadMode): Boolean; inline;
begin
  Result := ALoadMode in [lmPartialBurst, lmFullBurst];
end;

Usage:

pascal

if IsBurstLoadMode(Query.ActualLoadMode) then
  ShowMessage('Using burst mode - data pre-loaded');

GetTableNoLockDirective

Gets NOLOCK SQL hint for engine.

pascal

function GetTableNoLockDirective(AEngine: TInstantSQLEngine): string;
begin
  if AEngine = seMSSQL then
    Result := ' WITH(NOLOCK)'
  else
    Result := '';
end;

Usage:

pascal

var
  SQL: string;
begin
  SQL := 'SELECT * FROM Contacts' +
    GetTableNoLockDirective(Connector.SQLEngine);

  // SQL Server: "SELECT * FROM Contacts WITH(NOLOCK)"
  // Other DBs:  "SELECT * FROM Contacts"
end;

Common Usage Patterns

Type-Safe Attribute Definition

pascal

procedure DefineContactClass(Model: TInstantModel);
var
  ClassMeta: TInstantClassMetadata;
  Attr: TInstantAttributeMetadata;
begin
  ClassMeta := Model.ClassMetadatas.Add;
  ClassMeta.Name := 'TContact';
  ClassMeta.Persistence := peStored;
  ClassMeta.StorageName := 'CONTACTS';

  // Simple attribute
  Attr := ClassMeta.AttributeMetadatas.Add;
  Attr.Name := 'Name';
  Attr.AttributeType := atString;
  Attr.Size := 100;
  Attr.StorageKind := skEmbedded;

  // Date attribute
  Attr := ClassMeta.AttributeMetadatas.Add;
  Attr.Name := 'BirthDate';
  Attr.AttributeType := atDate;
  Attr.StorageKind := skEmbedded;

  // Reference attribute
  Attr := ClassMeta.AttributeMetadatas.Add;
  Attr.Name := 'Category';
  Attr.AttributeType := atReference;
  Attr.ObjectClassName := 'TCategory';
  Attr.StorageKind := skEmbedded;

  // Collection attribute
  Attr := ClassMeta.AttributeMetadatas.Add;
  Attr.Name := 'Phones';
  Attr.AttributeType := atParts;
  Attr.ObjectClassName := 'TPhone';
  Attr.StorageKind := skExternal;
  Attr.ExternalStorageName := 'ContactPhones';
end;

Load Mode Selection

pascal

function SelectLoadMode(ObjectCount: Integer): TInstantLoadMode;
begin
  if ObjectCount <= 100 then
    Result := lmFullBurst       // Small: load everything
  else if ObjectCount <= 1000 then
    Result := lmPartialBurst    // Medium: load simple attributes
  else
    Result := lmKeysFirst;      // Large: load keys only
end;

// Usage
Query.RequestedLoadMode := SelectLoadMode(EstimatedCount);

Engine-Specific SQL

pascal

function BuildQueryForEngine(AEngine: TInstantSQLEngine): string;
begin
  Result := 'SELECT * FROM Contacts';

  // Add engine-specific hints
  case AEngine of
    seMSSQL:
      Result := Result + ' WITH(NOLOCK)';
    seOracle:
      Result := Result + ' /*+ FIRST_ROWS */';
    // Add other engine-specific optimizations
  end;
end;

Best Practices

Use Appropriate Data Types
- dtString for varchar
- dtMemo for large text
- dtCurrency for money (not dtFloat)
- dtDate or dtTime when you don't need both
Choose Storage Kind Wisely
- skEmbedded for simple attributes and single references
- skExternal for Parts/References collections
- skVirtual for calculated properties
Load Mode Selection
- lmKeysFirst for large result sets (default)
- lmPartialBurst for grids showing simple data
- lmFullBurst for small sets needing all data
Error Handling
- Use TInstantErrorAction appropriately
- Don't use eaIgnore for critical operations
- Log errors with TInstantOperationType for context
Concurrency
- Use caFail (default) for optimistic locking
- Only use caIgnore when you're sure
- Handle EInstantConflict exceptions
SQL Engine
- Set correctly for optimal SQL generation
- Use engine-specific features when beneficial
- Test with target database

Version History

Version 3.0 - Initial type system
Version 3.5 - Added load modes
Version 4.0 - Enhanced SQL engine support
Version 4.2 - 64-bit types (IORefFieldType, TIORefValueType)
Version 4.3 - Additional enum support

InstantTypes ​

Overview ​

Type Definitions ​

Platform-Specific Types ​

Enumerations ​

TInstantAttributeType ​

TInstantAttributeCategory ​

TInstantDataType ​

TInstantStorageKind ​

TInstantPersistence ​

TInstantFieldOptions ​

TInstantOperationType ​

TInstantErrorAction ​

TInstantConflictAction ​

TInstantContentChangeType ​

TInstantLoadMode ​

TInstantSQLEngine ​

TInstantGraphicFileFormat ​

TInstantCatalogFeature ​

TInstantDBBuildCommandType ​

TInstantObjectNotification ​

TInstantVerificationResult ​

TInstantCacheNodeColor ​

Event Types ​

TInstantWarningEvent ​

Type Aliases ​

TInstantBytes ​

Helper Functions ​

IsBurstLoadMode ​

GetTableNoLockDirective ​

Common Usage Patterns ​

Type-Safe Attribute Definition ​

Load Mode Selection ​

Engine-Specific SQL ​

Best Practices ​

See Also ​

Version History ​

InstantTypes

Overview

Type Definitions

Platform-Specific Types

Enumerations

TInstantAttributeType

TInstantAttributeCategory

TInstantDataType

TInstantStorageKind

TInstantPersistence

TInstantFieldOptions

TInstantOperationType

TInstantErrorAction

TInstantConflictAction

TInstantContentChangeType

TInstantLoadMode

TInstantSQLEngine

TInstantGraphicFileFormat

TInstantCatalogFeature

TInstantDBBuildCommandType

TInstantObjectNotification

TInstantVerificationResult

TInstantCacheNodeColor

Event Types

TInstantWarningEvent

Type Aliases

TInstantBytes

Helper Functions

IsBurstLoadMode

GetTableNoLockDirective

Common Usage Patterns

Type-Safe Attribute Definition

Load Mode Selection

Engine-Specific SQL

Best Practices

See Also

Version History