VARCHAR2(size) Variable-length character string having a maximum of size bytes (up to 4000).
CHAR(size) Fixed-length character data, size characters long. Maximum size is 2000.
Default is 1 byte. Padded on the right with blanks to full length of size.
LENGTH(string) This tells the LENGTH of a string.
CHR(integer) CHR gives the character with an ASCII value equal to a given positive integer.
INSTR(string, set [, start [ ,occurrence ] ] )
INSTR finds the location of the beginning of a set of characters IN a STRing.
SUBSTR(string, start [,count])
SUBSTRing clips out a piece of a string beginning at start position and counting for count
characters from start.[@more@]
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