这些函数大部分返回VARCHAR2类型的数值.字符函数的返回类型所受的限制和基本数据库类型所受的限制是相同的,比如: VARCHAR2数值被限制为2000字符(ORACLE 8中为4000字符),而CHAR数值被限制为255字符(在ORACLE8中是2000).当在过程性语句中使用时,它们可以被赋值给VARCHAR2或者CHAR类型的PL/SQL变量....
1.IN- The parameter can be referenced by the procedure or function. The value of the parameter can not be overwritten by the procedure or function. 2.OUT- The parameter can not be referenced by the procedure or function, but the value of the parameter can be overwritten by the procedure ...
RATIO_TO_REPORT :该函数计算expression/(sum(expression))的值,它给出相对于总数的百分比 REGR_ (Linear Regression) Functions :这些线性回归函数适合最小二乘法回归线,有9个不同的回归函数可使用 代码语言:javascript 代码运行次数:0 运行 AI代码解释 四.行比较分析函数 LAG :可以访问结果集中的其它行而不用进...
Oracle University: Introduction to SQL Oracle University: SQL Workshop I Oracle University: SQL Workshop II YouTube channel: The Magic of SQL Related Analytical SQL Big Data SQL PL/SQL Query Optimization Statistical Functions Connect with Us OTN SQL Community MOSC SQL Language MOSC...
Oracle UNISTR Function With Examples (coming soon) Date and Time Functions ADD_MONTHS Returns a date value with a number of months added to it. ADD_MONTHS ( input_date, number_months ) Oracle ADD_MONTHS Function With Examples CURRENT_DATE Returns the current date in the session time zone. ...
在使用SQL提数的时候,常会遇到表内有重复值的时候,比如我们想得到 uv (独立访客),就需要做去重。 在MySQL中通常是使用 distinct 或 group by子句,但在支持窗口函数的 sql(如HiveSQL、Oracle等等) 中还可以使用 row_number 窗口函数进行去重。 举个栗子,现有这样一张表 task: ...
Oracle 11g PL/SQL Function Result Cache(原创) The PL/SQL Function Result Cache The PL/SQL function result cache uses the same infrastructure as the SQL query result cache, and caches the results of the PL/SQL functions in the result cache component of the SGA. Ideal candidates for caching ...
PASSING Clause for SQL Functions and Conditions Comparison and Sorting of JSON Data Type Values SQL/JSON Path Expression Item Methods See Also: JSON_TRANSFORM in Oracle Database SQL Language Reference CASE Expressionsin Oracle Database SQL Language Reference Parent topic: Insert, Update, and Load...
Home page for Oracle's Analytical SQL capabilities accessible in SQL. Oracle continues to expand its set of statistical functions available in Oracle 12c Database for use far beyond basic querying, supporting a wide range of features and functions: rank
开窗函数（Window Functions）是SQL中强大的分析工具，允许我们在不改变结果集行数的情况下进行复杂的聚合...