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Connect to SQLite database (FireDAC)

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Go Up to Database Connectivity (FireDAC)

This topic describes how to connect to SQLite database files.

Supported Versions

The FireDAC native driver supports SQLite database version 3.0 and later. For a detailed discussion on SQLite usage in FireDAC for a Delphi application, read the "Using SQLite with FireDAC" article.

Client Software

FireDAC supports two SQLite library linking modes:

  • Static linking -- the following client libraries are statically linked into the application:
    • Win32 - x86 sqlite3_x86.obj
    • Win64 - x64 sqlite3_x64.obj
    • OS X - x86 libcgsqlite3.dylib (requires deployment)
    • iOSDevice32 - libsqlite.a
    • iOSDevice64 - libsqlite.a
    • Android - libsqlite.a

FireDAC provides SQLite binaries v 3.9.2.

Note: SQLite database encryption is supported only for static linking.
  • Dynamic linking -- the following client libraries must be available in order to open a SQLite database:
    • Win32 - x86 SQLITE3.DLL
    • Win64 - x64 SQLITE3.DLL
    • OS X - libsqlite3.dylib
    • iOSDevice32 - libsqlite3.dylib
    • iOSDevice64 - libsqlite3.dylib
    • Android - libsqlite.so

We recommend you to use versions 3.7.7.1 or later. That is the default mode for iOS Simulator.

Note: SQLite engine comes pre-installed on all platforms but Windows. The library is compiled with limited column metadata capabilities by default (SQLITE_ENABLE_COLUMN_METADATA is undefined). As a result, FireDAC may fail to detect if the column auto-incremental mode is available or whether it is enabled or disabled.

You can download:

  • The latest x86 DLL version from here, Chapter "Precompiled Binaries For Windows", item "This is a DLL" and place it in a folder listed in your PATH environment variable (for example, System32 folder) or in your application EXE folder.
  • The x64 DLL version from here as "sqlite-netFx40-binary-x64-xxxxx.zip". Extract to a folder, copy SQLite.Interop.DLL into SQLITE3.DLL, then place it as above.

To choose the linking mode, you have to modify the FireDAC.inc file:

  • define FireDAC_SQLITE_STATIC for static linking.
  • undefine FireDAC_SQLITE_STATIC for dynamic linking.
Note: You can find the FireDAC.inc file under C:\Program Files (x86)\Embarcadero\Studio\18.0\source\data\firedac.

If the SQLite client library has not been installed properly, an exception is raised when you try to connect:

[FireDAC][Phys][SQLite]-314. Cannot load vendor library [SQLITE3.DLL]. The specified module could not be found. Check [SQLITE3.DLL], which is located in one of the PATH directories or in the application EXE directory.


Driver Linkage

To link the driver:

Connection Definition Parameters

To connect to a SQLite database, most applications require that you specify DriverID and Database (see Defining Connection (FireDAC) for details).

DriverID=SQLite

Parameter Description Example value
Database

A path to a database. Use ':memory:' or an empty string to create and connect to an empty in-memory database. A path can include path variables.

  • c:\MyApp\db.sdb
  • $(temp)\db.sdb
OpenMode

A mode to open a database:

  • CreateUTF8 -- open a database to read or write. If the database does not exist, it will be created with the UTF8 default encoding (the default value for pre-Delphi 2009).
  • CreateUTF16 -- open a database to read or write. If the database does not exist, it will be created with the UTF16 default encoding (the default value for Delphi 2009 and higher).
  • ReadWrite -- open a database to read or write. If the database does not exist, an exception is raised.
  • ReadOnly -- open a database to read only. If the database does not exist, an exception is raised.
ReadOnly
Encrypt Specifies a default encryption mode for a database. The mode may be overridden with an optional password prefix. If it is not specified, then the mode specified by this parameter is used. Otherwise, aes-256 is used.
Password Specifies a password for an encrypted database. The value may have the following form:

[ aes-128 | aes-192 | aes-256 | aes-ctr-128 | aes-ctr-192 | aes-ctr-256 | aes-ecb-128 | aes-ecb-192 | aes-ecb-256 :] <password> The optional prefix controls the cipher algorithm to be used. The default value is an empty string, which means the unencrypted mode.

  • aes-256:12345
  • qwe12345qwe
NewPassword

Specifies a new password for a database and performs an encryption operation:

  • To encrypt an unencrypted database, specify the non-empty NewPassword and empty Password;
  • To decrypt an encrypted database, specify the empty NewPassword and non-empty Password;
  • To change an encrypted database password, specify the non-empty NewPassword and non-empty Password.
BusyTimeout Sets an "ms" milliseconds to sleep when a table is locked and UpdateOptions.LockWait is set to True. Zero means do not wait. The default value is 10000. 5000
CacheSize Changes the maximum number of database disk pages that SQLite holds in memory at once. Each page uses about 1.5K of memory. The default value is 10000. 10000
SharedCache Enables or disables the SQLite shared cache feature. For more details, read this. The default value is True. False
LockingMode

Sets the database connection locking-mode. The value is one of the following:

  • Normal -- This mode gives multiuser access to database files.
  • Exclusive -- This mode gives maximum performance.

The default value is Exclusive, because it allows you to get maximum read/write speed for single user applications.

Exclusive
Synchronous

Sets the database connection synchronization mode of the in-memory cache with database files. The value is one of the following:

  • Full -- Synchronizes at every critical moment.
  • Normal -- As above, but less often.
  • Off -- Gives maximum performance. This is the default value.
Off
ForeignKeys

Enables foreign key usage for the database connection, when the application uses SQLite v 3.6.19 or later. The value is one of the following:

  • On -- Foreign keys in a session are enabled. This is the default value.
  • Off -- Foreign keys in a session are disabled.
Off
StringFormat

Defines how to represent String values:

  • Choose -- represent as ftString / ftWideString / ftMemo / ftWideMemo, depending on the declared data type name (default);
  • Unicode -- always represent as ftWideString / ftWideMemo;
  • ANSI -- always represent as ftString / ftMemo.
Unicode
GUIDFormat

Defines how to store GUID values:

  • String -- stores GUID as a character string value (default).
  • Binary -- stores GUID as a binary string value.
Binary
DateTimeFormat

Defines how to store date and time values:

  • String -- stores date and time as a character string value, using the YYYY-MM-DD and HH:MM:SS.XXX format (default).
  • Binary -- stores date and time as a real number, which is a Julian date.
  • DateTime -- stores date and time as a real number, which is a TDateTime value.
Binary
Extensions

Enables, disables, or specifies the SQLite engine extensions to load:

  • True -- enables extensions.
  • False -- disables extensions (default).
  • Otherwise, use a list of extensions to load in the form <library>[=<entry point>][;...].
MyExt.dll;FullTS.dll
SQLiteAdvanced Additional SQLite database connection options. For details, see the Pragma statements supported by SQLite. auto_vacuum = 1;page_size = 4096;temp_store = FILE
MetaDefCatalog Default database name. The Design time code excludes the catalog name from the object name if it is equal to MetaDefCatalog. Setting MetaDefCatalog does not change the current database in the SQLite session. The default value is 'MAIN'. MyDB

Use Cases

  • Connect to a local database in exclusive mode:
DriverID=SQLite
Database=$(FDHOME)\DB\Data\FDDemo.sdb
  • Connect to a shared database (it is not recommended to store SQLite databases on Windows shared folders for multi user read-write access):
DriverID=SQLite
Database=\\srv\mydb.sqlite
LockingMode=Normal
Synchronous=Normal
  • Encrypt an unencrypted database:
DriverID=SQLite
Database=$(FDHOME)\DB\Data\FDDemo.sdb
NewPassword=aes-256:123qwe
  • Open an encrypted database:
DriverID=SQLite
Database=c:\temp\test.db
Password=123qwe
  • Connect to an in-memory database:
DriverID=SQLite
Database=:memory:
  • Connect to a database file in the Documents folder on the iOS Device or iOS Simulator in exclusive mode:
DriverID=SQLite
Database=$(DOC)/test.sdb

See Also

Samples

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