在SQL语法里面,有unique和distinct两个关键字, unique是distinct的同义词,功能完全相同。 distinct是标准语法,其他数据库 sql server,db2,oracle,sybase,mysql等都支持。 unique,oracle、informix数据库认识,其他数据库有的认识,有的不认识。 以后方便数据库移植,推荐使用distinc
distinct怎么没起作用?作用是起了的,不过他同时作用了两个字段,也就是必须得id与name都相同的才会被排除。。。 我们再改改查询语句: select id, distinct name from table 很遗憾,除了错误信息你什么也得不到,distinct必须放在开头。难到不能把distinct放到where条件里?能,照样报错。 ——— 下面方法可行: selec...
DISTINCT_KEYS Decimal 不同的索引值数。对于强制使用 UNIQUE 和 PRIMARY KEY 约束的索引,此值与表中的行数相同 (USER_TABLES.NUM_ROWS)。 AVG_LEAF_BLOCKS_PER_KEY Decimal 平均叶块数,索引中的每个不同值舍入到最接近的整数。对于强制使用 UNIQUE 和 PRIMARY KEY 约束的索引,此值始终为 1。
SELECT DISTINCT ENTRY_TYPE, DESCR FROM PS_ENTRY_TYPE_TBL This query gives the transaction type codes in your Oracle Inventory application and their corresponding descriptions. The Oracle Inventory application is a data source from which Oracle General Ledger and Profitability Analytics extract data. ...
“up the stack” to focus on new, generally applicable product features rather than custom code linked to specific deployments with distinct customers. With service provisioning, product updates, and customer support all happening faster than ever, resources can be refocused on developing new features...
17-6 17.1.17 Alert Fires Multiple Times Using COUNTDISTINCT Aggregate... 17-6 17.1.18 Select Higher Time Groupings in Crosstab Views ... 17-7 17.1.19 Invoking an Oracle Data Integrator Scenario With Date Input From Oracle BAM Alert Rule ......
Deuxièmement, le stockage de blocs réduit la consommation d'énergie lorsque des disques durs magnétiques sont utilisés, car les disques ne tournent pas en même temps. Comme il n'existe pas de fichier distinct pour chaque bloc de stockage, les disques ne tournent que lorsque les donné...
We are studying the punctual structures, i.e., the primitive recursive structures on the whole set of integers. The punctual categoricity relative to a com
When a connection is opened, a connection pool is created based on an exact matching algorithm that associates the pool with the connection string in the connection. Each connection pool is associated with a distinct connection string. When a new connection is opened, if the connection string is...
Each SVM has a distinct namespace through which all of the NAS data shared from that SVM can be accessed. This namespace can be thought of as a map to all of the junctioned volumes for the SVM, regardless of the node or the aggregate on which they physically reside. Volumes can be ...