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mojunbin：
这个不能不顶。
《Pro Oracle SQL》 Chapter2--2.1 Oracle Architecture Basics -
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谢谢，获益匪浅
《Pro Oracle SQL》--chapter 5--5.6 Building Logical Expressions -
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《Pro Oracle SQL》--Chapter 5--5.4 Questions about the Question -
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谢谢
《Pro Oracle SQL》 翻译序 -- 读书心得 -
jiaoshiguoke：
继续 加油
《Pro Oracle SQL》--Chapter 6--6.1 Explain Plans--之三
文章列表
Lookup Tables 查找表
(page 290)
You can define a lookup table and refer to that lookup table in the rules section. Such a lookup table is
sometimes termed a reference table . Reference tables are defined in the initial section of the SQL
statement and then referred in the rules section ...
Iteration 迭代
(page 287)
Iteration provides another facility to implementing complex business requirements using a concise
Model SQL statement. A block of rules can be executed in a loop a certain number of times or while a
condition remains true. The syntax for the iteration is:
...
Aggregation 聚合
(page 285)
Data aggregation is commonly used in the data warehouse queries. The Model clause provides the
ability to aggregate the data using aggregate functions over the range of dimension columns.
数据聚合在数据仓库查询中很常用。 ...
Evaluation Order 求值顺序
(page 282)
Multiple rules can be specified in the rules section, and the rules can be specified with dependencies betweene them. The rule evaluation sequence can affect the functional behavior of the SQL statement, as you will see in this section. Furthermore, ev ...
Returning Updated Rows 返回更新的行
(page 280)
In Listing 9-7, just four rows were returned even though there are rows for other weeks. The clause
RETURN UPDATED ROWS controls this behavior and provides the ability to limit the cells returned by the
SQL statement. Without this clause, ...
Positional and Symbolic References 位置和符号引用
(page 277)
As discussed previously, the CV function provides the ability to refer to a single cell. It is also possible
to refer to an individual cell or group of cells using positional or symbolic notations. In addition, you
can write F ...
I
nter-Row Referencing via the Model clause 用Model子句行间引用
(page 274)
In a conventional SQL statement, emulating the spreadsheet described in Listing 9-1 is achieved by a
multitude of self-joins. With the advent of the Model clause, you can implement the spreadsheet
without self-joins be ...
The Model Clause Model子句
(page 273)
Riyaj Shamsudeen
The Model clause introduced in the Oracle Database version 10g provides an elegant method to
replace the spreadsheet. With the Model clause, it is possible to utilize powerful features such as
aggregation, parallelis ...
Outer Joins 外连接
(page 120)
An outer join returns all rows from one table and only those rows from the joined table where the join
condition is met.
Oracle uses the + character to indicate an outer join. The + is placed in parentheses
on the side of the join condition with ...
Cartesian Joins 笛卡尔连接
(page 118)
Cartesian joins occur when all the rows from one table are joined to all the rows of another table. Therefore, the total number of rows resulting from the join equals the number of rows from one table ( A) multiplied by the number of rows in the othe ...
Hash Joins 哈希连接
(page 116)
Hash joins, like sort-merge joins, first reads the two tables to be joined independently and applies the
criteria in the WHERE clause. Based on table and index statistics, the table that is determined to return the fewest rows will be hashed in its enti ...
Sort-Merge Joins 排序-合并连接
(page 114)
Sort-merge joins read the two tables to be joined independently, sorts the rows from each table (but only those rows that meet the conditions for the table in the WHERE clause) in order by the join key, and then merges the sorted rowsets.
The s ...
Nested Loops Joins 嵌套循环连接
(page 111)
Nested loops joins use each row of the query result reached through one access operation to drive into another table.
These joins are typically most effective if the result set is limited in size and indexes
are present on the columns used for ...
Join Methods 连接方法
(page 110)
If there are multiple tables in your query, after the optimizer determines the access methods most
appropriate for each of the tables, the next step is to determine the way the tables can best be joined
together and the proper order in which to ...
Index Fast Full Scan 索引快速全扫描
(page 109)
An index fast full scan is more like a full table scan than like other index scan types. When an index
fast full scan operation is chosen, all the index blocks are read using multiblock reads. This type of
scan is chosen as an alternative to a ...