一个Table表为空,怎么写代码?进来有分! 一个Table表为空,如何通过代码实现,请解答。 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 还是莫名奇妙,什么意思啊你?你究竟要创建一个Table为空、使一个存在的TABLE变成为空还是判断一个TABLE是否为空 在程序中,或能执行sql语句的地方,执行下面语句CREATE TABLE创建新表。语法CREATE TABLE [ database_name.[ owner ] .| owner.] table_name ( { < column_definition > | column_name AS computed_column_expression | < table_constraint > ::= [ CONSTRAINT constraint_name ] } | [ { PRIMARY KEY | UNIQUE } [ ,...n ] ) [ ON { filegroup | DEFAULT } ] [ TEXTIMAGE_ON { filegroup | DEFAULT } ] < column_definition > ::= { column_name data_type } [ COLLATE < collation_name > ] [ [ DEFAULT constant_expression ] | [ IDENTITY [ ( seed , increment ) [ NOT FOR REPLICATION ] ] ] ] [ ROWGUIDCOL] [ < column_constraint > ] [ ...n ] < column_constraint > ::= [ CONSTRAINT constraint_name ] { [ NULL | NOT NULL ] | [ { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] [ WITH FILLFACTOR = fillfactor ] [ON {filegroup | DEFAULT} ] ] ] | [ [ FOREIGN KEY ] REFERENCES ref_table [ ( ref_column ) ] [ ON DELETE { CASCADE | NO ACTION } ] [ ON UPDATE { CASCADE | NO ACTION } ] [ NOT FOR REPLICATION ] ] | CHECK [ NOT FOR REPLICATION ] ( logical_expression ) } < table_constraint > ::= [ CONSTRAINT constraint_name ] { [ { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] { ( column [ ASC | DESC ] [ ,...n ] ) } [ WITH FILLFACTOR = fillfactor ] [ ON { filegroup | DEFAULT } ] ] | FOREIGN KEY [ ( column [ ,...n ] ) ] REFERENCES ref_table [ ( ref_column [ ,...n ] ) ] [ ON DELETE { CASCADE | NO ACTION } ] [ ON UPDATE { CASCADE | NO ACTION } ] [ NOT FOR REPLICATION ] | CHECK [ NOT FOR REPLICATION ] ( search_conditions ) } 在程序中,或能执行sql语句的地方,执行下面语句CREATE TABLE创建新表。语法CREATE TABLE [ database_name.[ owner ] .| owner.] table_name ( { < column_definition > | column_name AS computed_column_expression | < table_constraint > ::= [ CONSTRAINT constraint_name ] } | [ { PRIMARY KEY | UNIQUE } [ ,...n ] ) [ ON { filegroup | DEFAULT } ] [ TEXTIMAGE_ON { filegroup | DEFAULT } ] < column_definition > ::= { column_name data_type } [ COLLATE < collation_name > ] [ [ DEFAULT constant_expression ] | [ IDENTITY [ ( seed , increment ) [ NOT FOR REPLICATION ] ] ] ] [ ROWGUIDCOL] [ < column_constraint > ] [ ...n ] < column_constraint > ::= [ CONSTRAINT constraint_name ] { [ NULL | NOT NULL ] | [ { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] [ WITH FILLFACTOR = fillfactor ] [ON {filegroup | DEFAULT} ] ] ] | [ [ FOREIGN KEY ] REFERENCES ref_table [ ( ref_column ) ] [ ON DELETE { CASCADE | NO ACTION } ] [ ON UPDATE { CASCADE | NO ACTION } ] [ NOT FOR REPLICATION ] ] | CHECK [ NOT FOR REPLICATION ] ( logical_expression ) } < table_constraint > ::= [ CONSTRAINT constraint_name ] { [ { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] { ( column [ ASC | DESC ] [ ,...n ] ) } [ WITH FILLFACTOR = fillfactor ] [ ON { filegroup | DEFAULT } ] ] | FOREIGN KEY [ ( column [ ,...n ] ) ] REFERENCES ref_table [ ( ref_column [ ,...n ] ) ] [ ON DELETE { CASCADE | NO ACTION } ] [ ON UPDATE { CASCADE | NO ACTION } ] [ NOT FOR REPLICATION ] | CHECK [ NOT FOR REPLICATION ] ( search_conditions ) } 我的意思是:怎样通过代码判断一个Table表是否为空。不好意思,我没说清楚,知道的请做答。 请问kk_wyx(桃花岛):你知道吗?请快回复,谢谢!! declare n int;begin select count(1) into n from 'your table'; if n = 0 then 表为空; end if;end ; 我是用C++Builder作为开发工具的,请详细给出代码怎么写。 sql如何让行在列上显示? 这个sql语句怎么写? SQL2008表中数据的单元格是只读属性,不能更改数据,请教怎么设置属性为非只读 top 1 返回值赋给变量怎么做 索引问题 急~求各位大侠帮忙 关于sql语句 如何保存表的信息,并将此信息导入 如何将某列数据拆分成多列? update问题 字段名称直接用中文好不好 Function-Based Indexes的问题 这个存储过程怎么写?(SQLSERVER7)
你究竟要
创建一个Table为空、
使一个存在的TABLE变成为空
还是判断一个TABLE是否为空
CREATE TABLE
创建新表。语法
CREATE TABLE
[ database_name.[ owner ] .| owner.] table_name
( { < column_definition >
| column_name AS computed_column_expression
| < table_constraint > ::= [ CONSTRAINT constraint_name ] } | [ { PRIMARY KEY | UNIQUE } [ ,...n ]
) [ ON { filegroup | DEFAULT } ]
[ TEXTIMAGE_ON { filegroup | DEFAULT } ] < column_definition > ::= { column_name data_type }
[ COLLATE < collation_name > ]
[ [ DEFAULT constant_expression ]
| [ IDENTITY [ ( seed , increment ) [ NOT FOR REPLICATION ] ] ]
]
[ ROWGUIDCOL]
[ < column_constraint > ] [ ...n ] < column_constraint > ::= [ CONSTRAINT constraint_name ]
{ [ NULL | NOT NULL ]
| [ { PRIMARY KEY | UNIQUE }
[ CLUSTERED | NONCLUSTERED ]
[ WITH FILLFACTOR = fillfactor ]
[ON {filegroup | DEFAULT} ] ]
]
| [ [ FOREIGN KEY ]
REFERENCES ref_table [ ( ref_column ) ]
[ ON DELETE { CASCADE | NO ACTION } ]
[ ON UPDATE { CASCADE | NO ACTION } ]
[ NOT FOR REPLICATION ]
]
| CHECK [ NOT FOR REPLICATION ]
( logical_expression )
} < table_constraint > ::= [ CONSTRAINT constraint_name ]
{ [ { PRIMARY KEY | UNIQUE }
[ CLUSTERED | NONCLUSTERED ]
{ ( column [ ASC | DESC ] [ ,...n ] ) }
[ WITH FILLFACTOR = fillfactor ]
[ ON { filegroup | DEFAULT } ]
]
| FOREIGN KEY
[ ( column [ ,...n ] ) ]
REFERENCES ref_table [ ( ref_column [ ,...n ] ) ]
[ ON DELETE { CASCADE | NO ACTION } ]
[ ON UPDATE { CASCADE | NO ACTION } ]
[ NOT FOR REPLICATION ]
| CHECK [ NOT FOR REPLICATION ]
( search_conditions )
}
CREATE TABLE
创建新表。语法
CREATE TABLE
[ database_name.[ owner ] .| owner.] table_name
( { < column_definition >
| column_name AS computed_column_expression
| < table_constraint > ::= [ CONSTRAINT constraint_name ] } | [ { PRIMARY KEY | UNIQUE } [ ,...n ]
) [ ON { filegroup | DEFAULT } ]
[ TEXTIMAGE_ON { filegroup | DEFAULT } ] < column_definition > ::= { column_name data_type }
[ COLLATE < collation_name > ]
[ [ DEFAULT constant_expression ]
| [ IDENTITY [ ( seed , increment ) [ NOT FOR REPLICATION ] ] ]
]
[ ROWGUIDCOL]
[ < column_constraint > ] [ ...n ] < column_constraint > ::= [ CONSTRAINT constraint_name ]
{ [ NULL | NOT NULL ]
| [ { PRIMARY KEY | UNIQUE }
[ CLUSTERED | NONCLUSTERED ]
[ WITH FILLFACTOR = fillfactor ]
[ON {filegroup | DEFAULT} ] ]
]
| [ [ FOREIGN KEY ]
REFERENCES ref_table [ ( ref_column ) ]
[ ON DELETE { CASCADE | NO ACTION } ]
[ ON UPDATE { CASCADE | NO ACTION } ]
[ NOT FOR REPLICATION ]
]
| CHECK [ NOT FOR REPLICATION ]
( logical_expression )
} < table_constraint > ::= [ CONSTRAINT constraint_name ]
{ [ { PRIMARY KEY | UNIQUE }
[ CLUSTERED | NONCLUSTERED ]
{ ( column [ ASC | DESC ] [ ,...n ] ) }
[ WITH FILLFACTOR = fillfactor ]
[ ON { filegroup | DEFAULT } ]
]
| FOREIGN KEY
[ ( column [ ,...n ] ) ]
REFERENCES ref_table [ ( ref_column [ ,...n ] ) ]
[ ON DELETE { CASCADE | NO ACTION } ]
[ ON UPDATE { CASCADE | NO ACTION } ]
[ NOT FOR REPLICATION ]
| CHECK [ NOT FOR REPLICATION ]
( search_conditions )
}
不好意思,我没说清楚,
知道的请做答。
你知道吗?请快回复,谢谢!!
n int;
begin
select count(1)
into n
from 'your table';
if n = 0 then
表为空;
end if;
end ;