Description: Return the Acsii value of the letter
For example: select Asc("A") returns 65
Description: Convert ascii value to character
For example: select chr(65) returns "A"
Description: Format string
For example: Select Format(now(),"yyyy-mm-dd") returns similar to "2008-04-03"
Select Format(3/9,"0.00") returns 0.33
Description: The query substring appears at the first location in the string, no 0 is returned.
For example: select Instr("abc","a") Return 1
Description: Return the lowercase form of the string
For example: select LCase("ABC") returns "abc"
Description: Left intercept string
For example: select Left("ABC",1) returns "A"
Description: Return the string length
For example: select Len("Hello ABC") returns 5
Description: Left-cut space
For example: select LTrim(" 111") returns "111"
Description: Get substring
For example: select mid("abcd",1,2) returns "ab"
Description: Right-handed string
For example: select Right("ABC",1) Returns "C"
Description: Snap the space right
For example: select Right("ABC") returns "ABC"
Description: Generate spaces
For example: select Space(5) returns 5 spaces
Description: Compare whether the contents of the two strings are consistent (case insensitive)
For example: select StrComp("abc","ABC") returns 0
select StrComp("abc","123") returns -1
Description: Intercept the spaces at both ends of the string
For example: select Trim(" ABC ") returns "ABC"
Description: Convert string to uppercase
For example: select UCase("abc") returns "ABC"