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介绍只包含表连接而没有聚合的物化视图。与聚合类似，表连接也是相当消耗资源的操作， 将其结果预先计算并存储于物化视图中，可以提高SQL执行效率。 每一个基表(包括inline view)的Rowid必须出现在物化视图的select部分。这也是该物化视图可以快速刷新的必要条件之一。其他条件包括：From&n...

Prebuilt MV alter table

MV Staleness Query_Rewrite_Integrity nonvalidated rely referential integrity

物化视图 快速刷新 DBMS_MVIEW DBMS_ADVISOR.TUNE_MVIEW explain_rewrite

Oracle Compound Trigger ORA-04091

IntroductionThe server result cache is a memory pool within the shared pool.When a query executes, the database looks in the cache memory to determine whether the result exists in the cache. If the result exists, then the database retrieves the result from memory instead of executing the query....

先上架构图：先决条件1. Oracle database 11g已安装，2. Oracle GoldenGate 11g for Linux已安装3. Oracle Data Integrator已安装在windows上环境介绍Oracle Linux 64 bit 6.4 (IP: 192.168.1.109),hosts both database and GoldenGate.Oracle Database: 11.2.0.3 64 bitOracle GoldenGate ...

The basic function gets a random number, greater than or equal to 0 and less than 1, with 38 digits to the right of the decimal (38-digit precision).Alternatively, you can get a random Oracle number x, where x is greater than or equal to low and less than high.SELECT DBMS_RANDOM.VALUE,DBMS_RANDOM...

Comma_to_table  和 Table_to_Comma，比较有用。以下是例子：DECLARE  v_len BINARY_INTEGER;  v_tab DBMS_UTILITY.UNCL_ARRAY;  v_idx BINARY_INTEGER;  v_str VARCHAR2(200);  BEGIN  DBMS_UTILITY.COMMA_TO_TABLE (    'a,b,c',  --每个元素必须符合Ora...

Specify DETERMINISTIC to indicate that the function returns the same result value whenever it is called with the same values for its arguments.You must specify this keyword if you intend to call the function in the expression of a function-based index or from the query of a materialized view that ...

1. Group-by，最简单的办法select owner from all_objects group by owner;2. 分析函数select owner from (select owner, row_number() over (partition by owner order by owner) rnfrom all_objects) where rn=1;

Oracle Sequence Cache Performance 性能

Oracle Linux NFS

快速

Oracle Imp Exp data pump

Oracle Arithmetic Function

model looping spreadsheet reference table ordered rule

Oracle SQL Model

Windowing rows range unbounded preceding following current_row

CTAS employs the direct path load, in other words, it skips loading data into buffer cache. PGA consumptionConsider two scenarios:a) Create table target as select * from source;The result of select statement is not saved in memory, Oracle writes it directly to di...