Key_name: PRIMARY - 索引名字 Seq_in_index: 1 - 索引中列顺序号从1开始 Column_name: ID - 索引列 Collation: A - 列怎样在索引中被排序 Cardinality: 6 - 索引中唯一值的数量 Sub_part: NULL Packed: NULL Null: Index_type: BTREE - 索引算法类型 Comment: Index_comment: 1 row in set (0.01 ...
SQL 复制 EXEC sp_describe_first_result_set N'SELECT b2 AS b3 FROM v', NULL, 1; 以下为部分结果集。展开表 is_hiddencolumn_ordinalnamesource_schemasource_tablesource_columnis_part_of_unique_key 0 1 b3 dbo t B1 0 1 2 a dbo t a 1...
is_identity_column bit 如果數據行是標識列,則傳回 1;如果不是,則傳回 0。 如果無法判斷數據行是標識列,則傳回NULL。 is_part_of_unique_key bit 如果數據行是唯一索引的一部分,則傳回 1(包括唯一和主要條件約束),如果不是,則傳回 0。 如果無法判斷數據行是唯一索引...
Statistics: Num rows: 1 Data size: 201 Basic stats: COMPLETE Column stats: NONE Limit Number of rows: 3 Statistics: Num rows: 1 Data size: 201 Basic stats: COMPLETE Column stats: NONE File Output Operator compressed: false Statistics: Num rows: 1 Data size: 201 Basic stats: COMPLETE Col...
Specifies that positioned updates or deletes made through the cursor don't succeed if the row was updated since being read into the cursor. SQL Server doesn't lock rows as they're read into the cursor. Instead, it uses comparisons of timestamp column values, or a checksum value, if the...
案例 会话一 会话二 会话三 select sleep(1800),id from sbtest1 where id=1; 注:休眠1800秒后查询id=1的记录 alter table sbtest1...add column city varchar(30); 注:由于会话一未执行完,仍旧持有MDL...
Returns NULL if it cannot be determined that the column is an identity column. is_part_of_unique_key bit Returns 1 if the column is part of a unique index (including unique and primary constraints) and 0 if it is not. Returns NULL if it cannot be determined that the column is part ...
Binary string values are copied as is for bytes in the range0x20to0x7E, and using\xhexadecimal encoding for bytes outside that range. For example, if a duplicate-key error occurs for an attempt to insert0x41CF9Finto aVARBINARYunique column, the resulting error message uses UTF-8 with some...
Binary string values are copied as is for bytes in the range0x20to0x7E, and using\xhexadecimal encoding for bytes outside that range. For example, if a duplicate-key error occurs for an attempt to insert0x41CF9Finto aVARBINARYunique column, the resulting error message uses UTF-8 with some...
The clients run the statement when you connect to an instance of SQL Server. For more information, see SET CURSOR_CLOSE_ON_COMMIT. You can determine this option's status by examining the is_cursor_close_on_commit_on column in the sys.databases catalog view or the IsCloseCursorsOnCommit...