solidDB Help : solidDB reference : ODBC: Data types : Converting data from SQL to C data types
  
Converting data from SQL to C data types
This section provides information about converting data from SQL to C data types.
When an application calls SQLFetch, SQLFetchScroll, or SQLGetData, the driver retrieves the data from the data source. If necessary, it converts the data from the data type in which the driver retrieved it to the data type specified by the TargetType argument in SQLBindCol or SQLGetData. Finally, it stores the data in the location pointed to by the TargetValuePtr argument in SQLBindCol or SQLGetData (and the SQL_DESC_DATA_PTR field of the ARD).
The following table shows the supported conversions from ODBC SQL data types to ODBC C data types.
▪ An asterisk (*) indicates the default conversion for an SQL data type (the C data type to which the data will be converted when the value of TargetType is SQL_C_DEFAULT).
▪ A hollow circle (o) indicates a supported conversion.
For an ODBC 3.x application working with an ODBC 2.x driver, conversion from driver-specific data types might not be supported.
 
SQL data type
C
H
A
R
W
C
H
A
R
S
T
I
N
Y
I
I
N
T
U
T
I
N
Y
I
N
T
T
I
N
Y
I
N
T
S
S
H
O
R
T
U
S
H
O
R
T
S
H
O
R
T
S
L
O
N
G
U
L
O
N
G
L
O
N
G
S
B
I
G
I
N
T
U
B
I
G
I
N
T
F
L
O
A
T
D
O
U
B
L
E
N
U
M
E
R
I
C
B
I
N
A
R
Y
D
A
T
E
T
I
M
E
T
I
M
E
S
T
A
M
P
SQL_CHAR
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
SQL_VARCHAR
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
SQL_LONGVARCHAR
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
SQL_WCHAR
o
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
SQL_WVARCHAR
o
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
SQL_WLONGVARCHAR
o
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
SQL_TINYINT (signed)
o
o
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
 
 
 
SQL_TINYINT (unsigned)
o
o
o
*
o
o
o
o
o
o
o
o
o
o
o
o
o
 
 
 
SQL_SMALLINT (signed)
o
o
o
o
o
*
o
o
o
o
o
o
o
o
o
o
o
 
 
 
SQL_SMALLINT (unsigned)
o
o
o
o
o
o
*
o
o
o
o
o
o
o
o
o
o
 
 
 
SQL_INTEGER (signed)
o
o
o
o
o
o
o
o
*
o
o
o
o
o
o
o
o
 
 
 
SQL_INTEGER (unsigned)
o
o
o
o
o
o
o
o
o
*
o
o
o
o
o
o
o
 
 
 
SQL_BIGINT (signed)
o
o
o
o
o
o
o
o
o
o
o
*
o
o
o
o
 
 
 
 
SQL_BIGINT (unsigned)
o
o
o
o
o
o
o
o
o
o
o
o
*
o
o
o
o
 
 
 
SQL_REAL
o
o
o
o
o
o
o
o
o
o
o
o
o
*
o
o
o
 
 
 
SQL_FLOAT
o
o
o
o
o
o
o
o
o
o
o
o
o
o
*
o
o
 
 
 
SQL_DOUBLE
o
o
o
o
o
o
o
o
o
o
o
o
o
o
*
o
o
 
 
 
SQL_DECIMAL
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
 
 
 
SQL_NUMERIC
*
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
 
 
 
SQL_BINARY
o
o
 
 
 
 
 
 
 
 
 
 
 
 
 
 
*
 
 
 
SQL_VARBINARY
o
o
 
 
 
 
 
 
 
 
 
 
 
 
 
 
*
 
 
 
SQL_LONGVARBINARY
o
o
 
 
 
 
 
 
 
 
 
 
 
 
 
 
*
 
 
 
SQL_TYPE_DATE
o
o
 
 
 
 
 
 
 
 
 
 
 
 
 
 
o
*
 
o
SQL_TYPE_TIME
o
o
 
 
 
 
 
 
 
 
 
 
 
 
 
 
o
 
*
o
SQL_TYPE_TIMESTAMP
o
o
 
 
 
 
 
 
 
 
 
 
 
 
 
 
o
o
o
*
The format of the converted data is not affected by the Windows country setting.
Although the table shows a wide range of ODBC conversions, including conversions involving unsigned data types, solidDB supports only signed, not unsigned, integer data types (SQL_TINYINT, SQL_SMALLINT, SQL_INTEGER, SQL_BIGINT). You can bind an unsigned C variable to a signed SQL column, but you must make sure that the values you store fit within the range supported by both data types.
solidDB does not support the BIT/SQL_BIT data type for SQL columns. However, you can bind a numeric SQL column to a BIT data type in your C application. For example, you can use a TINYINT column in your database and bind that column to a C variable of type SQL_C_BIT. The solidDB ODBC driver will try to convert numeric types in the database to BIT data types for the C variables. The numeric data values must be 1 or 0 or NULL; other values cause a data conversion error.
See
Data conversion tables from SQL to C
SQL to C data conversion examples
Go up to
ODBC: Data types