IF NOT EXISTS (SELECT 1 FROM KSQL_USERCOLUMNS WHERE KSQL_COL_TABNAME = 'T_BD_TAXUSEMAPBASE' AND KSQL_COL_NAME ='FBASEDATANUMBER') 
 ALTER TABLE T_BD_TAXUSEMAPBASE ADD (FBASEDATANUMBER NVARCHAR(100) DEFAULT ' ' NOT NULL );
 --- drop column --------- 不允许删除表T_BD_TAXUSEMAPBASE的字段FBASEDATANUMBER,请恢复pdm中的字段 ------------------- 

