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Funkce MS Access


MS Access má mnoho vestavěných funkcí.

Tento odkaz obsahuje funkce řetězce, čísel a data v MS Access.


Funkce řetězce MS Access

Function Description
Asc Returns the ASCII value for the specific character
Chr Returns the character for the specified ASCII number code
Concat with & Adds two or more strings together
CurDir Returns the full path for a specified drive
Format Formats a value with the specified format
InStr Gets the position of the first occurrence of a string in another
InstrRev Gets the position of the first occurrence of a string in another, from the end of string
LCase Converts a string to lower-case
Left Extracts a number of characters from a string (starting from left)
Len Returns the length of a string
LTrim Removes leading spaces from a string
Mid Extracts some characters from a string (starting at any position)
Replace Replaces a substring within a string, with another substring, a specified number of times
Right Extracts a number of characters from a string (starting from right)
RTrim Removes trailing spaces from a string
Space Returns a string of the specified number of space characters
Split Splits a string into an array of substrings
Str Returns a number as string
StrComp Compares two strings
StrConv Returns a converted string
StrReverse Reverses a string and returns the result
Trim Removes both leading and trailing spaces from a string
UCase Converts a string to upper-case


Číselné funkce MS Access

Function Description
Abs Returns the absolute value of a number
Atn Returns the arc tangent of a number
Avg Returns the average value of an expression
Cos Returns the cosine of an angle
Count Returns the number of records returned by a select query
Exp Returns e raised to the power of a specified number
Fix Returns the integer part of a number
Format Formats a numeric value with the specified format
Int Returns the integer part of a number
Max Returns the maximum value in a set of values
Min Returns the minimum value in a set of values
Randomize Initializes the random number generator (used by Rnd()) with a seed
Rnd Returns a random number
Round Rounds a number to a specified number of decimal places
Sgn Returns the sign of a number
Sqr Returns the square root of a number
Sum Calculates the sum of a set of values
Val Reads a string and returns the numbers found in the string

Funkce data MS Access

Function Description
Date Returns the current system date
DateAdd Adds a time/date interval to a date and then returns the date
DateDiff Returns the difference between two dates
DatePart Returns a specified part of a date (as an integer)
DateSerial Returns a date from the specified parts (year, month, and day values)
DateValue Returns a date based on a string
Day Returns the day of the month for a given date
Format Formats a date value with the specified format
Hour Returns the hour part of a time/datetime
Minute Returns the minute part of a time/datetime
Month Returns the month part of a given date
MonthName Returns the name of the month based on a number
Now Returns the current date and time based on the computer's system date and time
Second Returns the seconds part of a time/datetime
Time Returns the current system time
TimeSerial Returns a time from the specified parts (hour, minute, and second value)
TimeValue Returns a time based on a string
Weekday Returns the weekday number for a given date
WeekdayName Returns the weekday name based on a number
Year Returns the year part of a given date

MS Access Některé další funkce

Function Description
CurrentUser Returns the name of the current database user
Environ Returns a string that contains the value of an operating system environment variable
IsDate Checks whether an expression can be converted to a date
IsNull Checks whether an expression contains Null (no data)
IsNumeric Checks whether an expression is a valid number