odbc_binmode

odbc_binmode -- handling of binary column data

Description

int odbc_binmode(int result_id, int mode);

(ODBC SQL types affected: BINARY, VARBINARY, LONGVARBINARY)

When binary SQL data is converted to character C data, each byte (8 bits) of source data is represented as two ASCII characters. These characters are the ASCII character representation of the number in its hexadecimal form. For example, a binary 00000001 is converted to "01" and a binary 11111111 is converted to "FF".

Table 1. LONGVARBINARY handling

binmodelongreadlenresult
ODBC_BINMODE_PASSTHRU0passthru
ODBC_BINMODE_RETURN0passthru
ODBC_BINMODE_CONVERT0passthru
ODBC_BINMODE_PASSTHRU0passthru
ODBC_BINMODE_PASSTHRU>0passthru
ODBC_BINMODE_RETURN>0return as is
ODBC_BINMODE_CONVERT>0return as char

If odbc_fetch_into() is used, passthru means that an empty string is returned for these columns.

If result_id is 0, the settings apply as default for new results.

Note: Default for longreadlen is 4096 and binmode defaults to ODBC_BINMODE_RETURN. Handling of binary long columns is also affected by odbc_longreadlen()