The DELETE FROM statement deletes rows from a table in an external database, based on a search condition.
All rows for which the WHERE clause expression evaluates to TRUE are deleted from the table identified by TableReference.
Each row is examined in turn and a variable is set to point to the current row. Typically, the WHERE clause expression uses this variable to access column values and thus cause rows to be retained or deleted according to their contents. The variable is referred to by CorrelationName or, in the absence of an AS clause, by TableName.
If a schema name is not specified, the default schema for the broker's database user is used.
If a data source name is not specified, the database pointed to by the node's data source attribute is used.
The WHERE clause expression can use any of the broker’s operators and functions in any combination. It can refer to table columns, message fields, and any declared variables or constants.
However, be aware that the broker treats the WHERE clause expression by examining the expression and deciding whether the whole expression can be evaluated by the database. If it can, it is given to the database. In order to be evaluated by the database, it must use only those functions and operators supported by the database.
The WHERE clause can, however, refer to message fields, correlation names declared by containing SELECT functions, and to any other declared variables or constants within scope.
It is possible for errors to occur during delete operations. For example, the database may not be operational. In these cases, an exception is thrown (unless the node has its throw exception on database error property set to FALSE). These exceptions set appropriate SQL code, state, native error, and error text values and can be dealt with by error handlers (see the DECLARE HANDLER statement).
For further information about handling database errors, see Capturing database state.
DELETE FROM Database.SHAREHOLDINGS AS S WHERE S.ACCOUNTNO = InputBody.AccountNumber;
This removes all the rows from the SHAREHOLDINGS table where the value in the ACCOUNTNO column (in the table) is equal to that in the AccountNumber field in the message. This may delete zero, one, or more rows from the table.
-- Declare variables to hold the data source, schema, and table names and -- set their default values DECLARE Source CHARACTER 'Production'; DECLARE Schema CHARACTER 'db2admin'; DECLARE Table CHARACTER 'DynamicTable1'; -- Code which calculates their actual values comes here -- Delete rows from the table DELETE FROM Database.{Source}.{Schema}.{Table} As R WHERE R.Name = 'Joe';