HFSQL

they exist) from the server. HDeleteGroup Deletes (from the server) a group of users associated with a connection. HDeleteLink Deletes an integrity rule between two data files on the server. HDeleteScheduledOptimization Deletes a scheduled optimization task of HFSQL Client/Server data files. HDeleteParameter Deletes a parameter that was previously saved by HSavePara- meter. HDeleteDirectory Deletes a directory found in a HFSQL Client/Server database. HDeleteQuery Deletes a query (used by stored procedures) from a HFSQL server. HDeleteBackup Deletes a backup that was performed by HBackup. HDeleteScheduledBackup Deletes a scheduling for backup from a HFSQL Client/Server server. HDeleteTask Deletes a scheduled task from a HFSQL Client/Server server. HDeleteAll Deletes all records from a data file, a HFSQL view or a query. HDeleteUser Deletes a user associated with a connection from the sever HOnServerCall Customizes the management of message display on the client computer and the management of disconnection from a client computer. HOnError Customizes the management of HFSQL errors. HTransactionCancel If a transaction is in progress, cancels all the operations per- formed on the data files in transaction since the start of trans- action. HTransactionStart Starts a transaction on the HFSQL files and creates the transac- tion file. HTransactionEnd Validates the current transaction. HTransactionInterrupted Used to find out whether a transaction was interrupted (the transaction was neither validated nor canceled). HTransactionIsolation Configures the transaction isolation level for a connection to a given HFSQL server. HTransactionFree Transforms all the “in transaction” records into “Normal” records if they do not belong to an ongoing transaction. HTransactionList Returns the list of current or interrupted transactions found on the server for the specified connection. HSortView Sorts a view by creating an index on a view item. HFound Checks whether the current record corresponds to the current filter or to the current search. HCheckIndex Checks whether the data found in the index file (.NDX file) properly refers the data found in the data file (.FIC file). HCheckStructure Defines the mode for comparing data files. HToFile Copies a data source (file, query, view, ...) to a physical HFSQL file with the same description. This file is neither encrypted nor password protected. HVersion Allows you to find out whether the file’s content was modified. HToItem Assigns the specified value to an item of the current record. HViewToFile Saves the modifications made to a view in the corresponding file. VOCABULARY The vocabulary varies based on the interlocutors. The same concept is often described using different words. Different standards, different practices, side by side! Let’s see a small glossary of the terms used in databases. PC SOFT vocabulary Other publishers Analysis (CDM, LDM) Schema, relational model, entity/rela- tionship model Analysis chart Template of schema Data File Table Item Column, Field (a field is the intersection of a column and a row) Record Line, tuple, row Link Relation Lock Lock Key Index Unique key Primary key Key with duplicates Foreign key or key without uniqueness constraint Link Item Foreign key Window Form Control Control Report Report Viewing table Datagrid, Browse Scheduled task Scheduler Text memo Lob or clob Binary Memo Lob or blob Stored procedure UDF (User Defined Function) A database is a set of tables (files) linked via relationships (links). A table ( data file ) is a set of data organized in columns (items), made of rows (records) The intersection of a row and a column is a field (item value). An index is a way to accelerate searches, queries and accesses to a table. An index can be defined on a column (key item) or on several columns (composite key). A primary key is a unique key that can’t be null. A foreign key is a key that accepts duplicates , used jointly with a primary key to establish a relationship (link) between 2 tables. HFSQL • www.windev.com 21