{ ***************************************************************************

Copyright (c) 2016-2020 Kike Pérez

Unit : Quick.DAO.QueryGenerator.SQLite

Description : Core Entity SQLite Query Generator

Author : Kike Pérez

Version : 1.0

Created : 22/11/2019

Modified : 11/09/2020

This file is part of QuickCore: https://github.com/exilon/QuickCore

***************************************************************************

Licensed under the Apache License, Version 2.0 (the "License");

you may not use this file except in compliance with the License.

You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software

distributed under the License is distributed on an "AS IS" BASIS,

WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and

limitations under the License.

*************************************************************************** }

unit Quick.Core.Entity.QueryGenerator.SQLite;

{$i QuickCore.inc}

interface

uses

Classes,

SysUtils,

Quick.Commons,

Quick.Core.Entity.DAO;

type

TSQLiteQueryGenerator = class(TEntityQueryGenerator,IEntityQueryGenerator)

private

fFormatSettings : TFormatSettings;

public

function Name : string;

constructor Create;

function CreateTable(const aTable : TEntityModel) : string;

function ExistsTable(aModel : TEntityModel) : string;

function ExistsColumn(aModel : TEntityModel; const aFieldName : string) : string;

function AddColumn(aModel : TEntityModel; aField : TEntityField) : string;

function SetPrimaryKey(aModel : TEntityModel) : string;

function CreateIndex(aModel : TEntityModel; aIndex : TEntityIndex) : string;

function Select(const aTableName, aFieldNames : string; aLimit : Integer; const aWhere : string; aOrderFields : string; aOrderAsc : Boolean) : string;

function Sum(const aTableName, aFieldName, aWhere: string): string;

function Count(const aTableName : string; const aWhere : string) : string;

function Add(const aTableName: string; const aFieldNames, aFieldValues : string) : string;

function AddOrUpdate(const aTableName: string; const aFieldNames, aFieldValues : string) : string;

function Update(const aTableName, aFieldPairs, aWhere : string) : string;

function Delete(const aTableName : string; const aWhere : string) : string;

function DateTimeToDBField(aDateTime : TDateTime) : string;

function DBFieldToDateTime(const aValue : string) : TDateTime;

function QuotedStr(const aValue: string): string; override;

function DBFieldToGUID(const aValue : string) : TGUID;

function GUIDToDBField(aGuid : TGUID) : string;

end;

implementation

const

{$IFNDEF FPC}

DBDATATYPES : array of string = ['varchar(%d)','text','char(%d)','integer','integer','bigint','decimal(%d,%d)','bit','date','time','datetime','datetime','datetime','varchar(38)'];

{$ELSE}

DBDATATYPES : array[0..10] of string = ('varchar(%d)','text','char(%d)','integer','integer','bigint','decimal(%d,%d)','bit','date','time','datetime','datetime','datetime','varchar(38)');

{$ENDIF}

{ TSQLiteQueryGenerator }

function TSQLiteQueryGenerator.AddColumn(aModel: TEntityModel; aField: TEntityField) : string;

var

datatype : string;

querytext : TStringList;

begin

querytext := TStringList.Create;

try

querytext.Add(Format('ALTER TABLE [%s]',[aModel.TableName]));

if aField.DataType = dtFloat then

begin

datatype := Format(DBDATATYPES[Integer(aField.DataType)],[aField.DataSize,aField.Precision])

end

else

begin

if aField.DataSize > 0 then datatype := Format(DBDATATYPES[Integer(aField.DataType)],[aField.DataSize])

else datatype := DBDATATYPES[Integer(aField.DataType)];

end;

querytext.Add(Format('ADD [%s] %s',[aField.Name,datatype]));

Result := querytext.Text;

finally

querytext.Free;

end;

end;

constructor TSQLiteQueryGenerator.Create;

begin

{$IFDEF DELPHIRX103_UP}

fFormatSettings := TFormatSettings.Create;

{$ELSE}

GetLocaleFormatSettings(0,fFormatSettings);

{$ENDIF}

fFormatSettings.ShortDateFormat := 'YYYY-MM-DD';

fFormatSettings.ShortTimeFormat := 'hh:nn:ss';

fFormatSettings.DateSeparator := '-';

fFormatSettings.TimeSeparator := ':';

end;

function TSQLiteQueryGenerator.CreateIndex(aModel: TEntityModel; aIndex: TEntityIndex) : string;

begin

Result := Format('CREATE INDEX IF NOT EXISTS PK_%s ON %s (%s)',[aIndex.FieldNames[0],aModel.TableName,aIndex.FieldNames[0]]);

end;

function TSQLiteQueryGenerator.CreateTable(const aTable: TEntityModel) : string;

var

field : TEntityField;

datatype : string;

querytext : TStringList;

begin

querytext := TStringList.Create;

try

querytext.Add(Format('CREATE TABLE IF NOT EXISTS [%s] (',[aTable.TableName]));

for field in aTable.Fields do

begin

if field.DataType = dtFloat then

begin

datatype := Format(DBDATATYPES[Integer(field.DataType)],[field.DataSize,field.Precision])

end

else

begin

if field.DataSize > 0 then datatype := Format(DBDATATYPES[Integer(field.DataType)],[field.DataSize])

else datatype := DBDATATYPES[Integer(field.DataType)];

end;

if field.IsPrimaryKey then

begin

if field.DataType = dtAutoID then querytext.Add(Format('[%s] %s PRIMARY KEY AUTOINCREMENT,',[field.Name,datatype]))

else querytext.Add(Format('[%s] %s PRIMARY KEY,',[field.Name,datatype]));

end

else

begin

if field.DataType = dtCreationDate then querytext.Add(Format('[%s] %s DEFAULT CURRENT_TIMESTAMP,',[field.Name,datatype]))

else querytext.Add(Format('[%s] %s,',[field.Name,datatype]));

end;

end;

querytext[querytext.Count-1] := Copy(querytext[querytext.Count-1],1,querytext[querytext.Count-1].Length-1);

querytext.Add(')');

Result := querytext.Text;

finally

querytext.Free;

end;

end;

function TSQLiteQueryGenerator.ExistsColumn(aModel : TEntityModel; const aFieldName : string) : string;

begin

Result := Format('PRAGMA table_info(%s)',[aModel.TableName]);

end;

function TSQLiteQueryGenerator.ExistsTable(aModel: TEntityModel): string;

begin

Result := Format('SELECT name FROM sqlite_master WHERE type = ''table'' AND name = ''%s''',[aModel.TableName]);

end;

function TSQLiteQueryGenerator.Name: string;

begin

Result := 'SQLITE';

end;

function TSQLiteQueryGenerator.QuotedStr(const aValue: string): string;

begin

Result := '"' + aValue + '"';

end;

function TSQLiteQueryGenerator.SetPrimaryKey(aModel: TEntityModel) : string;

begin

Result := '';

Exit;

end;

function TSQLiteQueryGenerator.Sum(const aTableName, aFieldName, aWhere: string): string;

var

querytext : TStringList;

begin

querytext := TStringList.Create;

try

querytext.Add(Format('SELECT SUM (%s) FROM [%s] WHERE %s',[aTableName,aFieldName,aWhere]));

Result := querytext.Text;

finally

querytext.Free;

end;

end;

function TSQLiteQueryGenerator.Select(const aTableName, aFieldNames : string; aLimit: Integer;

const aWhere: string; aOrderFields: string; aOrderAsc: Boolean) : string;

var

orderdir : string;

querytext : TStringList;

begin

querytext := TStringList.Create;

try

//define select-where clauses

if aFieldNames.IsEmpty then querytext.Add(Format('SELECT * FROM [%s] WHERE %s',[aTableName,aWhere]))

else querytext.Add(Format('SELECT %s FROM [%s] WHERE %s',[aFieldNames,aTableName,aWhere]));

//define orderby clause

if not aOrderFields.IsEmpty then

begin

if aOrderAsc then orderdir := 'ASC'

else orderdir := 'DESC';

querytext.Add(Format('ORDER BY %s %s',[aOrderFields,orderdir]));

end;

//define limited query clause

if aLimit > 0 then querytext.Add('LIMIT ' + aLimit.ToString);

Result := querytext.Text;

finally

querytext.Free;

end;

end;

function TSQLiteQueryGenerator.Add(const aTableName: string; const aFieldNames, aFieldValues : string) : string;

var

querytext : TStringList;

begin

querytext := TStringList.Create;

try

querytext.Add(Format('INSERT INTO [%s]',[aTableName]));

querytext.Add(Format('(%s)',[aFieldNames]));

querytext.Add(Format('VALUES(%s)',[aFieldValues]));

Result := querytext.Text;

finally

querytext.Free;

end;

end;

function TSQLiteQueryGenerator.AddOrUpdate(const aTableName: string; const aFieldNames, aFieldValues : string) : string;

var

querytext : TStringList;

begin

querytext := TStringList.Create;

try

querytext.Add(Format('INSERT OR REPLACE INTO [%s]',[aTableName]));

querytext.Add(Format('(%s)',[aFieldNames]));

querytext.Add(Format('VALUES(%s)',[aFieldValues]));

Result := querytext.Text;

finally

querytext.Free;

end;

end;

function TSQLiteQueryGenerator.Update(const aTableName, aFieldPairs, aWhere : string) : string;

var

querytext : TStringList;

begin

querytext := TStringList.Create;

try

querytext.Add(Format('UPDATE [%s]',[aTableName]));

querytext.Add(Format('SET %s',[aFieldPairs]));

querytext.Add(Format('WHERE %s',[aWhere]));

Result := querytext.Text;

finally

querytext.Free;

end;

end;

function TSQLiteQueryGenerator.Count(const aTableName : string; const aWhere : string) : string;

begin

Result := Format('SELECT COUNT(*) AS cnt FROM [%s] WHERE %s',[aTableName,aWhere]);

end;

function TSQLiteQueryGenerator.DateTimeToDBField(aDateTime: TDateTime): string;

begin

if fISO8601DateTime then Result := FormatDateTime('YYYY-MM-DD"T"HH:NN:SS',aDateTime)

else Result := FormatDateTime('YYYY-MM-DD hh:nn:ss',aDateTime);

end;

function TSQLiteQueryGenerator.DBFieldToDateTime(const aValue: string): TDateTime;

var

fmtdate : TFormatSettings;

begin

if fISO8601DateTime then

begin

fmtdate := fFormatSettings;

fmtdate.LongDateFormat := 'YYYY-MM-DDThh:nn:ss';

Result := StrToDateTime(aValue,fmtdate);

end

else Result := StrToDateTime(aValue,fFormatSettings);

end;

function TSQLiteQueryGenerator.Delete(const aTableName, aWhere: string) : string;

begin

Result := Format('DELETE FROM [%s] WHERE %s',[aTableName,aWhere]);

end;

function TSQLiteQueryGenerator.DBFieldToGUID(const aValue: string): TGUID;

begin

//Result := StringToGUID(aValue);

if aValue.Contains('{') then Result := StringToGUID(aValue)

else Result := StringToGUID('{' + aValue + '}');

end;

function TSQLiteQueryGenerator.GUIDToDBField(aGuid: TGUID): string;

begin

Result := aGuid.ToString;

end;

end.