LOWER

INSERT INTO local_test VALUES

(TO_TIMESTAMP(LOCALTIMESTAMP, ’DD-MON-RR HH.MI.SSXFF’));

The following statement uses the correct format mask to match the return type of

LOCALTIMESTAMP:

INSERT INTO local_test VALUES

(TO_TIMESTAMP(LOCALTIMESTAMP, ’DD-MON-RR HH.MI.SSXFF PM’));

LOG

Syntax log::=

LOG ( m , n )

Purpose

LOG returns the logarithm, base m, of n. The base m can be any positive number other than 0 or 1 and n can be any positive number.

Examples

The following example returns the log of 100:

SELECT LOG(10,100) "Log base 10 of 100" FROM DUAL;

Log base 10 of 100

------------------

2

LOWER

Syntax lower::=

LOWER ( char )

Functions 6-91

LPAD

Purpose

LOWER returns char, with all letters lowercase. char can be any of the datatypes

CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB, or NCLOB. The return value is the same datatype as char.

Examples

The following example returns a string in lowercase:

SELECT LOWER(’MR. SCOTT MCMILLAN’) "Lowercase"

FROM DUAL;

Lowercase

--------------------

mr. scott mcmillan

LPAD

Syntax lpad::=

Purpose

LPAD returns char1, left-padded to length n with the sequence of characters in char2; char2 defaults to a single blank. If char1 is longer than n, then this function returns the portion of char1 that fits in n.

Both char1 and char2 can be any of the datatypes CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB, or NCLOB. The string returned is of VARCHAR2 datatype and is in the same character set as char1.

The argument n is the total length of the return value as it is displayed on your terminal screen. In most character sets, this is also the number of characters in the return value. However, in some multibyte character sets, the display length of a character string can differ from the number of characters in the string.

Examples

The following example left-pads a string with the characters "*" and ".":

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LTRIM

SELECT LPAD(’Page 1’,15,’*.’) "LPAD example"

FROM DUAL;

LPAD example

---------------

*.*.*.*.*Page 1

LTRIM

Syntax ltrim::=

Purpose

LTRIM removes characters from the left of char, with all the leftmost characters that appear in set removed; set defaults to a single blank. If char is a character literal, then you must enclose it in single quotes. Oracle begins scanning char from its first character and removes all characters that appear in set until reaching a character not in set and then returns the result.

Both char and set can be any of the datatypes CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB, or NCLOB. The string returned is of VARCHAR2 datatype and is in the same character set as char.

Examples

The following example trims all of the left-most x’s and y’s from a string:

SELECT LTRIM(’xyxXxyLAST WORD’,’xy’) "LTRIM example"

FROM DUAL;

LTRIM example

------------

XxyLAST WORD

Functions 6-93

MAKE_REF

MAKE_REF

Syntax make_ref::=

Purpose

MAKE_REF creates a REF to a row of an object view or a row in an object table whose object identifier is primary key based.

See Also:

■Oracle9i Application Developer’s Guide - Fundamentals for more information about object views

■DEREF on page 6-58

Examples

The sample schema oe contains an object view oc_inventories based on inventory_typ. The object identifier is product_id. The following example creates a REF to the row in the oc_inventories object view with a product_id of 3003:

SELECT MAKE_REF (oc_inventories, 3003) FROM DUAL;

MAKE_REF(OC_INVENTORIES,3003)

------------------------------------------------------------------

00004A038A0046857C14617141109EE03408002082543600000014260100010001

00290090606002A00078401FE0000000B03C21F040000000000000000000000000

0000000000

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MAX

MAX

Syntax max::=

See Also: "Analytic Functions" on page 6-10 for information on syntax, semantics, and restrictions

Purpose

MAX returns maximum value of expr. You can use it as an aggregate or analytic function.

If you specify DISTINCT, then you can specify only the query_partition_ clause of the analytic_clause. The order_by_clause and windowing_ clause are not allowed.

See Also:

Aggregate Example

The following example determines the highest salary in the hr.employees table:

SELECT MAX(salary) "Maximum" FROM employees;

Maximum

----------

24000

Analytic Example

The following example calculates, for each employee, the highest salary of the employees reporting to the same manager as the employee.

Functions 6-95

MAX

SELECT manager_id, last_name, salary,

MAX(salary) OVER (PARTITION BY manager_id) AS mgr_max FROM employees;

If you enclose this query in the parent query with a predicate, then you can determine the employee who makes the highest salary in each department:

SELECT manager_id, last_name, salary

FROM (SELECT manager_id, last_name, salary,

MAX(salary) OVER (PARTITION BY manager_id) AS rmax_sal FROM employees) WHERE salary = rmax_sal;

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MIN

MIN

Syntax min::=

See Also: "Analytic Functions" on page 6-10 for information on syntax, semantics, and restrictions

Purpose

MIN returns minimum value of expr. You can use it as an aggregate or analytic function.

If you specify DISTINCT, then you can specify only the query_partition_ clause of the analytic_clause. The order_by_clause and windowing_ clause are not allowed.

See Also:

Aggregate Example

The following statement returns the earliest hire date in the hr.employees table:

SELECT MIN(hire_date) "Earliest" FROM employees;

Earliest

---------

17-JUN-87

Analytic Example

The following example determines, for each employee, the employees who were hired on or before the same date as the employee. It then determines the subset of employees reporting to the same manager as the employee, and returns the lowest salary in that subset.

Functions 6-97

MOD

SELECT manager_id, last_name, hire_date, salary,

MIN(salary) OVER(PARTITION BY manager_id ORDER BY hire_date

RANGE UNBOUNDED PRECEDING) as p_cmin

FROM employees;

.

.

MOD

Syntax mod::=

MOD ( m , n )

Purpose

MOD returns the remainder of m divided by n. Returns m if n is 0.

Examples

The following example returns the remainder of 11 divided by 4:

SELECT MOD(11,4) "Modulus" FROM DUAL;

Modulus

----------

3

This function behaves differently from the classical mathematical modulus function when m is negative. The classical modulus can be expressed using the MOD function with this formula:

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