Tài liệu Oracle Unleashed- P23 ppt

Data Type Conversion Functions You use the CDBL function to convert a string or expression into a value of data type Double.. You use the CINT function to convert a string or expression

The dimension of the array to examine (default is 1)

The return value is of the Integer data type

You use the UBOUND function to return the highest subscript defined for the specified dimension of an array

UBOUND ( array [, dimension] )

array The name of the array to examine

dimension

The dimension of the array to examine (default is 1)

The return value is of the Integer data type

Data Type Conversion Functions

You use the CDBL function to convert a string or expression into a value of data type Double

CDBL ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the Double data type

You use the CINT function to convert a string or expression into a value of data type Integer

CINT ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the Integer data type

You use the CLNG function to convert a string or expression into a value of data type Long

CLNG ( expression )

Can be any valid Oracle Basic variable or expression

The return value is of the Long data type

You use the CSNG function to convert a string or expression into a value of data type Single

CSNG ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the Single data type

You use the CSTR function to convert a string or expression into a value of data type String

CSTR ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the String data type

You use the CVDATE function to convert a string or expression into a value of data type Date

CVDATE ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the Date data type

You use the FIX function to convert a numeric expression into an integer by truncating its fractional part

FIX ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the Integer data type

You use the INT function to convert a numeric expression into an integer by rounding to the nearest value The rounding operation uses the absolute value of the expression to perform the round operation and then reapplies the sign of the original expression to the rounded value

INT ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the Integer data type

You use the STR function to convert a number or numeric expression into a value of data type String STR provides a leading space for positive numbers

STR ( expression )

expression

Can be any valid Oracle Basic variable or expression

The return value is of the String data type

Date Functions

You use the DATE function to return the current system date of your operating system as a String data type No

arguments are required

DATE ()

The return value is of the String data type

You use the DATEADD function to return a time or date value as the result of adding any number of time intervals to a date variable or expression

DATEADD ( time_interval, num_interval, date )

time_interval A string expression that indicates the type of time interval to add to the date.

s or S—Second

n or N—Minute

h or H—Hour

The date to add the time intervals to.

The return value is of the Date data type

You use the DATEDIFF function to return the number of time intervals between two specified dates

DATEDIFF ( time_interval, first_date, second_date )

time_interval A string expression that indicates the type of time interval to add to the date.

first_date A valid Oracle Basic date variable or expression

second_date

A valid Oracle Basic date variable or expression

The return value is of the Date data type

You use the DATEPART function to return the portion of a date value that corresponds to a specified time interval

DATEPART ( time_interval, date )

time_interval A string expression that indicates the type of time interval to add to the date.

A valid Oracle Basic date variable or expression

The return value is of the Date data type

You use the DATESERIAL function to return the complete date with integer arguments representing year, month, and day

DATESERIAL ( year, month, day )

year An integer representing the year

month An integer representing the month.

day

An integer representing the day

The return value is of the Date data type

You use the DAY function to return a long value between 1 and 31 representing the day portion of the specified date value

DAY ( date )

date

A valid Oracle Basic date variable or expression

The return value is of the Long data type

You use the HOUR function to return an integer value between 0 (12:00 a.m.) and 23 (11:00 p.m.) representing the hour portion of the specified date value

HOUR ( date )

date

A valid Oracle Basic date variable or expression

The return value is of the String data type

You use the MINUTE function to return an integer value between 0 and 59 representing the minute portion of the specified date value

MINUTE ( date )

date

A valid Oracle Basic date variable or expression

The return value is of the Integer data type

You use the MONTH function to return an integer value between 1 and 12 representing the month portion of the

specified date value

MONTH ( date )

date

A valid Oracle Basic date variable or expression

The return value is of the Integer data type

You use the NOW function to return the current system date of your operating system as a Date data type No arguments are required

NOW ()

The return value is of the Date data type

You use the SECOND function to return an integer value between 0 and 59 representing the second portion of the specified date value

SECOND ( date )

date

A valid Oracle Basic date variable or expression

The return value is of the Integer data type

You use the SYSDATE function to return the current system date of your operating system as a Date data type It is identical to the NOW function No arguments are required

SYSDATE ()

The return value is of the Date data type

You use the TIME function to return the current system time of your operating system as a String data type No

arguments are required

TIME ()

The return value is of the String data type

You use the TIMESERIAL function to return the complete time with integer arguments representing hour, minute, and second

TIMESERIAL ( hour, minute, second )

hour An integer representing the hour

minute An integer representing the minute.

second

An integer representing the second

The return value is of the Date data type

You use the TIMEVALUE function to convert a string into a date return value

TIMEVALUE ( time_value )

time_value

A valid Oracle Basic date variable or expression representing a time value

The return value is of the Date data type

You use the WEEKDAY function to return an integer value between 1 (Sunday) and 7 (Saturday) representing the day

of the week portion of the specified date value

WEEKDAY ( date )

date

A valid Oracle Basic date variable or expression

The return value is of the Integer data type

You use the YEAR function to return an integer between 99 and 10,000, inclusive, that represents the year portion of the specified date value

YEAR ( date )

A valid Oracle Basic date variable or expression

The return value is of the Integer data type

File Input and Output Functions

You use the CURDIR function to return the current path for the default drive (volume)

CURRDIR [[(] vol_id [)]]

vol_id

A string representing the drive or volume to search

The return value is of the String data type

You use the EOF function to test if the file pointer is at the end-of-file marker for the indicated file handle

EOF ( filenum )

filenum An integer number between 1 and 256 representing a file handle as a result of opening a file using the OPEN

command

The return value is of the Integer data type

You use the FREEFILE function to return an integer value between 1 and 256, inclusive, representing the next unused file number No arguments are required

FREEFILE ()

The return value is of the Integer data type

You use the INPUT function to return a string of characters read from a file opened in the input or binary mode

INPUT ( n, filenum )

n The number of characters to read from the file

filenum An integer number between 1 and 256 representing a file handle as a result of opening a file using the OPEN

command

The return value is of the String data type

You use the LOC function to return the current location of the file pointer for the indicated file handle

LOC ( filenum )

filenum An integer number between 1 and 256 representing a file handle as a result of opening a file using the OPEN

command

The return value is of the Positive Integer data type

You use the LOF function to return the length (in bytes) of the specified file handle

LOF ( filenum )

filenum An integer number between 1 and 256 representing a file handle as a result of opening a file using the OPEN

command

The return value is of the Positive Integer data type

You use the SEEK function to return the position of the next input or output operation for the specified file handle

double-DDB ( asset_cost, salvage, life, period )

asset_cost The initial value paid for the asset.

salvage The projected value of the asset at the end of its life expectancy

life The length of time the asset is expected to be useful

The length of time to calculate the asset's depreciation over

The return value is of the Double data type

You use the FV function to return the future value of an asset, such as an annuity, using a constant interest rate and constant periodic payments

FV ( rate, periods, payment, pv, due_end )

rate The fixed interest rate you estimate that you will be paying over the life of the annuity

periods The total number of payment periods over the life of the annuity

payment The fixed amount of the periodic payment.

pv The amount of the annuity

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

The return value is of the Double data type

You use the IPMT function to return the amount applied to interest from a specified periodic payment on an annuity at a fixed interest rate and fixed periodic payments

IPMT ( rate, which_period, periods, pv, fv, due_end )

rate The fixed interest rate you estimate that you will be paying over the life of the annuity

which_period The period to calculate the amount applied to principal.

periods The total number of payment periods over the life of the annuity

pv The amount of the annuity

fv The amount of the annuity to be unpaid at the end of the life of the annuity

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

The return value is of the Double data type

You use the IRR function to return the internal rate of return for an investment, which is its rate of return based on a series of periodic cash flows, both payments and receipts

IRR ( cash_flow_array, estimate )

cash_flow_array An array that contains the values of a series of payments and receipts over the life of an investment

There must be at least one payment and one receipt

estimate

The fixed interest rate you estimate that you will be using over the life of the cash flow

The return value is of the Double data type

You use the MIRR function to return the modified internal rate of return on an investment, which is the rate of return represented by a series of periodic cash flows (payments and receipts) when the interest rates for payments and receipts are different

MIRR ( cash_flow_array, borrow_rate, reinvest_rate )

cash_flow_array An array that contains the values of a series of payments and receipts over the life of an investment

There must be at least one payment and one receipt

borrow_rate The interest rate you pay to borrow money

reinvest_rate

The interest rate you expect to earn when reinvesting cash received

The return value is of the Double data type

You use the NPER function to return the number of periods for an annuity with fixed interest rates and fixed periodic payments

NPER ( rate, periods, pv, fv, due_end )

rate The fixed interest rate you estimate that you will be paying over the life of the annuity

periods The total number of payment periods over the life of the annuity

pv The amount of the annuity

fv The amount of the annuity to be unpaid at the end of the life of the annuity.

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

The return value is of the Double data type

You use the NPV function to return the net present value of an investment using a constant discount rate and a series of cash flow values (payments and receipts)

NPV ( discount_rate, cash_flow_array )

discount_rate The discount rate that applies over the whole period being considered

cash_flow_array An array that contains the values of a series of payments and receipts over the life of an investment

There must be at least one payment and one receipt

The return value is of the Double data type

You use the PMT function to return the payment for an annuity with a fixed interest rate and fixed periodic payment

PMT ( rate, periods, pv, fv, due_end )

rate The fixed interest rate you estimate that you will be paying over the life of the annuity

periods The total number of payment periods over the life of the annuity

pv The amount of the annuity

fv The amount of the annuity to be unpaid at the end of the life of the annuity

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

The return value is of the Double data type

You use the PPMT function to return the amount applied to the principal during one payment period for an annuity

PPMT ( rate, which_period, periods, pv, fv, due_end )

rate The fixed interest rate you estimate that you will be paying over the life of the annuity.

which_period The period to calculate the amount applied to principal.

periods The total number of payment periods over the life of the annuity

pv The amount of the annuity

fv The amount of the annuity to be unpaid at the end of the life of the annuity

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

The return value is of the Double data type

You use the PV function to return the present value of an annuity with a fixed interest rate and fixed periodic payments

PV ( rate, periods, payment, fv, due_end )

rate The fixed interest rate you estimate that you will be paying over the life of the annuity

periods The total number of payment periods over the life of the annuity

payment The fixed amount of the periodic payment.

fv The amount of the annuity to be unpaid at the end of the life of the annuity

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

The return value is of the Double data type

You use the RATE function to return the interest rate per period for an annuity

RATE ( periods, payment, pv, fv, due_end, estimate )

periods The total number of payment periods over the life of the annuity

payment The fixed amount of the periodic payment.

pv The amount of the annuity.

fv The amount of the annuity to be unpaid at the end of the life of the annuity

due_end 0 indicates that payments are due at the end of each period 1 indicates that payments are due at the

beginning of each period

estimate

The fixed interest rate you estimate that you will be paying over the life of the annuity

The return value is of the Double data type

You use the SLN function to return the depreciation of an asset's value for a single period using the straight-line method

SLN ( asset_cost, salvage, life )

asset_cost The initial value paid for the asset.

salvage The projected value of the asset at the end of its life expectancy

life

The length of time the asset is expected to be useful

The return value is of the Double data type

You use the SYD function to return the depreciation of an asset for a specified period using the sum-of-years-digits method

SYD ( asset_cost, salvage, life, period )

asset_cost The initial value paid for the asset.

salvage The projected value of the asset at the end of its life expectancy

life The length of time the asset is expected to be useful

period

The length of time to calculate the asset's depreciation over

The return value is of the Double data type

General Functions

You use the ENVIRON function to return the string that corresponds to a specified Windows operating system

environment variable This function returns NULL on the Macintosh

ENVIRON ( environment )

environment

A string variable or expression that is an environment variable, such as PATH

The return value is of the String data type

You use the HEX function to return a string value representing the hexadecimal value (base 16) for a decimal or numeric expression (base 10)

HEX ( numeric_expression )

numeric_expression

Any valid Oracle Basic number or numeric expression

The return value is of the String data type

You use the OCT function to return a string value representing the octal value (base 8) for a decimal or numeric

expression (base 10)

OCT ( numeric_expression )

numeric_expression

Any valid Oracle Basic number or numeric expression

The return value is of the String data type

You use the PAGENUM function to return the number of the page being printed from within a report No arguments are required

PAGENUM ()

The return value is of the Integer data type

You use the RND function to return a single precision number in the range 0 <= x < 1

RND ( [ctrl_num] )