Calculating the Size of Field Buffers

Table 9-3 through Table 9-6 summarize the memory requirements for each data type. "L" is the length specified in the control file. "P" is precision. "S" is the size of the length indicator. For more information about these values, see "SQL*Loader Data Types".

Table 9-3 Fixed-Length Fields

Data Type	Size in Bytes (Operating System-Dependent)
`INTEGER`	The size of the `INT` data type, in C
`INTEGER(N)`	`N` bytes
`SMALLINT`	The size of `SHORT INT` data type, in C
`FLOAT`	The size of the `FLOAT` data type, in C
`DOUBLE`	The size of the `DOUBLE` data type, in C
`BYTEINT`	The size of `UNSIGNED CHAR`, in C
`VARRAW`	The size of `UNSIGNED SHORT`, plus 4096 bytes or whatever is specified as `max_length`
`LONG VARRAW`	The size of `UNSIGNED INT`, plus 4096 bytes or whatever is specified as `max_length`
`VARCHARC`	Composed of 2 numbers. The first specifies length, and the second (which is optional) specifies `max_length` (default is 4096 bytes).
`VARRAWC`	This data type is for `RAW` data. It is composed of 2 numbers. The first specifies length, and the second (which is optional) specifies `max_length` (default is 4096 bytes).

Table 9-4 Nongraphic Fields

Data Type	Default Size	Specified Size
(packed) `DECIMAL`	None	(N+1)/2, rounded up
`ZONED`	None	P
`RAW`	None	L
`CHAR` (no delimiters)	1	L + S
datetime and interval (no delimiters)	None	L + S
numeric `EXTERNAL` (no delimiters)	None	L + S

Table 9-5 Graphic Fields

Data Type	Default Size	Length Specified with POSITION	Length Specified with DATA TYPE
`GRAPHIC`	None	L	2*L
`GRAPHIC EXTERNAL`	None	L - 2	2*(L-2)
`VARGRAPHIC`	4KB*2	L+S	(2*L)+S

Table 9-6 Variable-Length Fields

Data Type	Default Size	Maximum Length Specified (L)
`VARCHAR`	4 KB	L+S
`CHAR` (delimited)	255	L+S
datetime and interval (delimited)	255	L+S
numeric `EXTERNAL` (delimited)	255	L+S