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Funzioni di accesso MS


MS Access ha molte funzioni integrate.

Questo riferimento contiene le funzioni stringa, numerica e data in MS Access.


Funzioni delle stringhe di 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


Funzioni numeriche di 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

Funzioni data di accesso MS

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 Accedere ad alcune altre funzioni

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