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TCustomIBCQuery Class |
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TCustomIBCQuery Class |
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A base class for defining functionality for descendant classes which access database using SQL statements.
For a list of all members of this type, see TCustomIBCQuery members.
TCustomIBCQuery = class(TCustomIBCDataSet);
TCustomIBCQuery is a base class that defines functionality for descendant classes which access database using SQL statements. Applications never use the TCustomIBCQuery objects directly. Instead they use descendants of TCustomIBCQuery, such as TIBCQuery, TIBCStoredProc and TIBCTable.
TCustomIBCQuery implements functionality to update database tables using DML SQL statements. Put SQL statements into SQLInsert, SQLDelete, SQLUpdate properties. There is no restriction on their syntax, so any SQL statements are allowed. Usually you need to use INSERT, DELETE and UPDATE statements but also you can use stored procedures in more diverse cases.
SQLInsert, SQLDelete, SQLUpdate, SQLLock, SQLRefresh properties support automatic binding of parameters which have names identical to fields captions. To retrieve the value of a field as it was before operation use the field name with 'OLD_'. This is especially useful when doing field comparisons in the WHERE clause of the statement. Use TCustomDADataSet.BeforeUpdateExecute event to assign value to additional parameters and TCustomDADataSet.AfterUpdateExecute event for reading them.
TCustomIBCQuery is read-only when none of SQLInsert, SQLDelete, SQLUpdate properties are defined.
TMemDataSet
TCustomDADataSet
TCustomIBCDataSet
TCustomIBCQuery