INSERT INTO SC_U(Sno,Cno,OldGrade,NewGrade) VALUES(OldTuple.Sno,OldTuple.Cno,OldTuple.Grade,NewTuple.Grade) [例5.22] 将每次对表Student的插入操作所增加的学生个数 记录到表StudentInsertLog中。 CREATE TRIGGER Student_Count AFTER INSERT ON Student REFERENCING NEW TABLE AS DELTA FOR EACH STATEMENT ...
此外,CREATE TABLE 和ALTER TABLE 语句可用于设置 PRIMARY KEY 和UNIQUE 约束上的锁定粒度。 对于后向兼容,还可以使用 sp_indexoption 系统存储过程设置粒度。 若要显示给定索引的当前锁定选项,请使用 INDEXPROPERTY 函数。 可以禁止将页级锁、行级锁或页级锁和行级锁都用于指定的索引。
For unique indexes, the valid range of prefix length values is from 1 to the number of key columns minus 1. The default prefix length is the number of key columns minus 1. For nonunique indexes, the valid range of prefix length values is from 1 to the number of key columns. The defa...
In most cases you would also want to attach a UNIQUE or PRIMARY KEY constraint to prevent duplicate values from being inserted unexpectedly. Lastly, the sequence is marked as "owned by" the column, so that it will be dropped if the column or table is dropped. Currently, the SERIAL column...
ADD PARTITION statements), unless you explicitly override that value in the PARTITION clause of the statement that creates the partition.If you omit this clause, then Oracle uses the following default values:PCTFREE: 10 PCTUSED: 40 INITRANS: 1 MAXTRANS: Depends on data block size See Also: ...
FOR EACH STATEMENT INSERT INTO StudentInsertLog (Numbers) SELECT COUNT(*) FROM DELTA 1. 2. 3. 4. 5. 6. 7. T-SQL version --新建表StudentInsertLog,存储学生人数 CREATE TABLE StudentInsertLog ( Numbers INT ) --新建表StudentInsertLogUser,存储用户名和操作时间 ...
Use the CREATE FUNCTION FROM statement to access a user-defined function whose CREATE FUNCTION statement resides in a separate file. CREATE INDEX statement Use the CREATE INDEX statement to create an index for one or more columns in a table, or on values returned by a UDR that uses column ...
(EquipmentID, ErrorNumber, EventDesc) VALUES (248, 82, 'Feeder jam') ; INSERT Audit.StartStopEvents (EquipmentID, StartOrStop) VALUES (248, 1) ; INSERT Audit.ProcessEvents (EventCode, Description) VALUES (1841, 'Central feed in bypass mode.') ; -- The following statement comb...
sql_statement_recompile扩展事件 (XEvent) 报告语句级重新编译。 当任何类型的批处理需要语句级重新编译时,会发生此 XEvent。 这包括存储过程、触发器、即席批处理和查询。 可通过几个接口来提交批处理,这类接口包括 sp_executesql、动态 SQL、“准备”方法或“执行”方法。
Can we alias name for temp table Can we creating index on non unique value columns on temporary tables Can we do MAX inside nested CASE Statement? Can we generate pipe delimited column through SQL query Can we optimise While Loop in sql server for large number of data? Can we pass paramet...