Hello, everybody.
Please, find attached prerelease of zmsql 0.1.14.
Please, test it and report if you find bugs, before uploaded to ccr.
Main changes:
* Internal optimizations.
* Based on TZMBufDataset instead TBufDataset, because problems with current TBufDataset version.
* ZMQueryDataset now loads from and saves to files with .csv extension, instead of .txt extension.
* Added ManageFields method, which decides what to do with Fields and FieldDefs.
* Reworked InspectFields procedure, better deduction of FieldDefs and Fields status.
* Enabled automatic creation of persistent fields objects from predefined fielddefs.
* New published properties: DynamicFieldsCreated, PeristentFieldsCreated, MemoryDataSetOpened,
* New public methods: CreateDynamicFieldsFromFieldDefs, CreatePersistentFieldsFromFieldDefs;
Here are declarations of public methods and published properties (besides those inherited from TBufDataset), along with explainations:
public
{ Public declarations }
procedure QueryExecute; //Executes SQL query defined in SQL property, on .csv files that are placed in folder defined in ZMConnection property. Resultset of select query is loaded into the the zmquerydataset (self).
procedure PrepareQuery; //Prepares parameterized queries for execution: replaces parameters with parameter values for parameterized queries.
procedure EmptyDataSet; //Deletes all records from dataset.
procedure ClearDataSet; //Deletes records, fields and fielddefs.
procedure CopyFromDataset (pDataset:TDataSet); //Copies schema and data from any TDataset.
function SortDataset (const pFieldName:String):Boolean; //Ascending/Descending sorting of memory dataset.
procedure LoadFromTable; //Loads data (or data and schema) from a .csv file (TableName.csv), set in property TableName, from path specified in ZMConnection property.
procedure SaveToTable;overload; //Saves data and schema to a .csv file (TableName.csv), set in Tablename property, in path specified in ZMConnection property.
procedure SaveToTable(pDecimaSeparator:Char);overload; //Saves data and schema to a .csv file (TableName.csv), set in Tablename property, in path specified in ZMConnection property.
procedure CreateDynamicFieldsFromFieldDefs; // Creates fields from predefined fielddefs. To be used in design-time or run-time for memory dataset creation according to predefined fielddefs.
procedure CreatePersistentFieldsFromFieldDefs; // Creates PERSISTENT fields from predefined fielddefs. To be used in design-time only.
procedure MemoryDataSetOpen; //Executes CreateDynamicFieldsFromFieldDefs and set dataset to Active.
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
//Properties needed for master/detail and referential integrity
property MasterDataSetTo:TList read FMasterDataSetTo write SetMasterDataSetTo; // Defines master/detail relationship for purpose of master/detail filtration
property MasterReferentialKeys:TList read FMasterReferentialKeys write SetMasterReferentialKeys;//Defines master/detail relationship for purpose of referential integrity
property SlaveReferentialKeys:TList read FSlaveReferentialKeys write SetSlaveReferentialKeys; //Defines master/detail relationship for purpose of referential integrity
property DisableMasterDetailFiltration:Boolean read FDisableMasterDetailFiltration write SetDisableMasterDetailFiltration; //Master/detail filrtation should be temporarily desabled during bulk inserts or updates...
property OldRecord:TZMBufDataSet {TBufDataSet} read FOldRecord; //Last delete/insert/edit is preserved in this property.
published
{ Published declarations }
property ZMConnection:TZMConnection read FZMConnection write SetConnection; //Defines "database" folder path where .csv tables are placed. Instantiates JanSQL database engine.
property SQL:TStrings read FSQL write SetSQL; //Unprepared SQL query text.
property QueryExecuted:Boolean read FQueryExecuted write SetQueryExecuted; //"True" executes QueryExecute and loads resultset into dataset.
property TableName:String read FTableName write SetTableName; //Name of .csv file (without extension) from which is data loaded by LoadFromTable and to which is data and schema saved by SaveToTable.
property TableLoaded:Boolean read FTableLoaded write SetTableLoaded; //"True" executes LoadFromTable and loads resultset into dataset.
property TableSaved:Boolean read FTableSaved write SetTableSaved; //"True" executes SaveToTable and saves dataset to .csv file defined in TableName property, placed in folder specified by ZMConnection property.
property DynamicFieldsCreated:Boolean read FDynamicFieldsCreated write SetDynamicFieldsCreated; //"True" executes CreateDynamicFieldsFromFieldDefs, which creates fields from predefined fielddefs.
property PeristentFieldsCreated:Boolean read FPersistentFieldsCreated write SetPersistentFieldsCreated; //"True" executes CreatePersistentFieldsFromFieldDefs, which creates PERSISTENT fields from predefined fielddefs.
property MemoryDataSetOpened:Boolean read FMemoryDataSetOpened write SetMemoryDataSetOpened; //"True" executes CreateDynamicFieldsFromFieldDefs and activates dataset for editing.
property PersistentSave:Boolean read FPersistentSave write SetPersistentSave; //If "True", insert/delete/edit will immediately be written to underlying .csv file. If "False", then dataset is only in-memory.
property Parameters: TParams read FParameters write SetParameters; //Parameters for parameterized SQL text.
//Master/detail filtration
property MasterFields: TStrings read FMasterFields write SetMasterFields; //Fields in masterdatasource, (separated by ";") to be used for master/detail filtration.
property MasterSource: TDataSource read FMasterSource write SetMasterSource;//Master datasource for master/detail filtration.
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