Oracle PL/SQL/Numeric Math Functions/LN

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LN: Returns natural logs, that is, logs with respect to base e

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SQL> SQL> -- create demo table SQL> create table TestTable(

 2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
 3    MyName             VARCHAR2(10 BYTE),
 4    MyDate             DATE,
 5    MyNumber           Number(8,2)
 6  )
 7  /

Table created. SQL> SQL> SQL> insert into TestTable (ID, MyName, MyDate, MyNumber) values("1","Alison",to_date("19960711","YYYYMMDD"),12.12); 1 row created. SQL> insert into TestTable (ID, MyName, MyDate, MyNumber) values("1","Alison",to_date("19970622","YYYYMMDD"),2.12); 1 row created. SQL> insert into TestTable (ID, MyName, MyDate, MyNumber) values("1","Alison",to_date("19980513","YYYYMMDD"),22.1); 1 row created. SQL> insert into TestTable (ID, MyName, MyDate, MyNumber) values("1","Alison",to_date("19990624","YYYYMMDD"),2.12); 1 row created. SQL> insert into TestTable (ID, MyName, MyDate, MyNumber) values("1","Alison",to_date("20000415","YYYYMMDD"),2.1); 1 row created. SQL> SQL> SQL> select * from TestTable

 2

SQL> SQL> SQL> --LN: Returns natural logs, that is, logs with respect to base e. SQL> SELECT LN(MyNumber) FROM TestTable; LN(MYNUMBER)


 2.49485698
 .751416089
 3.09557761
 .751416089
 .741937345

SQL> SQL> SQL> SQL> SQL> drop table TestTable;

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LN(x):Returns the natural logarithm of x

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SQL> -- SQL> SQL> --LN(x):Returns the natural logarithm of x. SQL> SQL> select LN(2.71828183) from dual; LN(2.71828183)


            1

SQL>

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