已解决: nested exception is java.sql.SQLDataException: ORA-01476: divisor is equal to zero 问题 oracle 除零异常,且sql重复语句过多 思路 使用decode 或者 NULLIF 解决除零异常问题 原SQL case when冗余 可以用 case when in 简化 解决 在这个修改后的SQL语句中,NULLIF函数用于处理zzje、zxjje和jxjje计算...
Oracle nested table功能介绍如下 http://www.orafaq.com/wiki/NESTED_TABLE NESTED TABLE is an Oracle data type used to support columns containing multivalued attributes, in this case, columns that can hold an entire sub-table. Create a table with NESTED TABLE column: CREATEOR REPLACETYPEmy_tab_...
oracle除零异常,且sql重复语句过多 思路 使用decode 或者 NULLIF 解决除零异常问题 原SQL case when冗余 可以用 case when in 简化 解决 在这个修改后的SQL语句中,NULLIF函数用于处理zzje、zxjje和jxjje计算中的被零除错误。如果分母为零,则NULLIF函数返回NULL,防止被零除的错误。
3.The OPTIMIZER_FEATURES_ENABLE initialization parameter is set to a release before Oracle Database 11g. In this case, Oracle Database uses the original implementation for nested loop joins. 没有11g的环境,以后可以注意一下。最近看了一些sql调优化的例子,总结出嵌套循环的使用情况: 通常情况下驱动表(...
MySQL (and Oracle) use 'CROSS' because it fits in the LEFT/RIGHT data source table identifier scheme, MsSQL uses 'FULL' to be descriptive of the operation. Other than that it's a bit like quibbling over rowset vs recordset, They are simply labels for the same thing. Perhaps I should...
使用nested sets 将比使用一个遍历adjacency list的储存过程更快,对于天生缺乏递归的查询结构也是更快的选择。比如MySQL.但是递归SQL查询语句也能提供类似“迅速查询后代”的语句并且在其他深度搜索查询是更快,所以也是对于提供这一功能的数据库的更快选择。例如PostgreSQL,[5]Oracle,[6]andMicrosoft SQL Server.[7] ...
参考网址:http://sql-plsql.blogspot.com/2011/09/difference-nested-correlated-subquery.html http://www.java2s.com/Tutorial/Oracle/0040__Query-Select/WritingNestedSubqueries.htm http://www.java2s.com/Tutorial/Oracle/0040__Query-Select/WritingCorrelatedSubqueries.htm ...
Istruzioni SQL supportate per la condivisione dei dati, scritture sui consumatori. Istruzioni SQL non supportate per la condivisione dei dati, scritture sui consumatori. Disponibile Regioni AWS Nozioni di base Guida introduttiva alla condivisione dei dati in sola lettura nella console Connessione a un...
下 总结:1、配置数据源-ds.xml数据源文件 2、配置数据库驱动到jboss_home/server/default/libjava代码连接数据库方法:// 如果部署在jboss上面,前面要加...一、Jboss端配置JNDI数据源Jboss安装目录 docexamplesjca 下有各种如oracle,db2,sqlserver等数据库JNDI配置的模板文件,形式为“数据库 ...
例如 PostgreSQL,[5] Oracle,[6] and Microsoft SQL Server.[7] 缺点 The use case for a dynamic endless database tree hierarchy is rare. The Nested Set model is appropriate where the tree element and one or two attributes are the only data, but is a poor choice when more complex ...