How to call "Vacuum" from Delphi code

[JayM]

I need to call Vacuum in Delphi code (Delphi 2007, LiteDac Professional 1.6.4, registered). During development, I am not using "Direct Mode" but eventually I will use this as database needs to be encrypted.

I have seen the following code on one of the forum posts.

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PRAGMA page_size=16384;
VACUUM;

My Data Module "Uses" the following units but obviously that is not enough:
DB, DBAccess, LiteAccess, MemDS

I have TLiteConnection and TLiteQuery components on the Data Module. (No other LiteDac components are on Data Module.)

In which unit are Vacuum and PRAGMA_xyz declared?
Which object does the "Vacuum" procedure/function belong to, if any?

Thank You

JayM

[AlexP]

Hello,

PRAGMA and VACUUM are the SQLite commands, therefore they are absent in our modules. So, to run them, you can use any components allowing to run commands, for example:

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  LiteConnection1.ExecSQL('PRAGMA page_size=16384');
  LiteConnection1.ExecSQL('VACUUM');

or

Code: Select all

  LiteQuery1.SQL.Text := 'PRAGMA page_size=16384';
  LiteQuery1.Execute;
  LiteQuery1.SQL.Text := 'VACUUM';
  LiteQuery1.Execute;

[JayM]

Thank you very much.

I am posting SIMILAR question regarding how to call "Repair", "ReIndex" and "Backup" from Delphi code. If there is documentation regarding these issues, please point me in the right direction so that I stop bothering you on the forum.

[AlexP]

Hello,

The REINDEX method can be called similarly to the PRAGMA and VACUUM methods. For the time being, the SQLite Online Backup API engine is not implemented in LiteDAC. Therefore, presently, to restore the DB, you can use the SQLite3.exe console utility.