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WORM 0.2
A C++ DAL/ORM code generation framework
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WORM 0.2
A C++ DAL/ORM code generation framework
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WSqlDataType namespace - flags for supported SQL data types. More...
WSqlDataType namespace - flags for supported SQL data types.
This is a container for type flags and convenience functions for the supported SQL datatypes.
These are the ANSI SQl standard types supported by WSQL - these will be mapped to native C++ data types in ORM class generation. For example a TINYINT column will declared as a member of type "short", a VARCHAR or TEXT as type std::string, a DECIMAL to a double, etc. The following is a list of the types with specifications - Implementers of drivers should use this as a guide for translating types for a particular DBMS.
Writers of drivers should translate any proprietary or other data types specific to the DBMS of the driver to these types. Most DBMS metadata is returned in a string identifier of one of these types and can usually be mapped conveniently by using the functions toString(type) or toType(string).
See the following for more information on the specific data types:
Note: these types are modeled after the MySQL data types (which seemed the broadest
and closest to ANSI standard). I include these notes for reference only - they are
for determining how types will be converted..(todo)
TINYINT - A very small integer that can be signed or unsigned. If signed, the
allowable range is from -128 to 127. If unsigned, the allowable range is from 0
to 255. You can specify a width of up to 4 digits.
SMALLINT - A small integer that can be signed or unsigned. If signed, the
allowable range is from -32768 to 32767. If unsigned, the allowable range is
from 0 to 65535. You can specify a width of up to 5 digits.
MEDIUMINT - A medium-sized integer that can be signed or unsigned. If signed,
the allowable range is from -8388608 to 8388607. If unsigned, the allowable
range is from 0 to 16777215. You can specify a width of up to 9 digits.
INT - A normal-sized integer that can be signed or unsigned. If signed, the
allowable range is from -2147483648 to 2147483647. If unsigned, the allowable
range is from 0 to 4294967295. You can specify a width of up to 11 digits.
BIGINT - A large integer that can be signed or unsigned. If signed, the
allowable range is from -9223372036854775808 to 9223372036854775807. If
unsigned, the allowable range is from 0 to 18446744073709551615. You can specify
a width of up to 11 digits.
FLOAT(M,D) - A floating-point number that cannot be unsigned. You can define the
display length (M) and the number of decimals (D). This is not required and will
default to 10,2, where 2 is the number of decimals and 10 is the total number of
digits (including decimals). Decimal precision can go to 24 places for a FLOAT.
DOUBLE(M,D) - A double precision floating-point number that cannot be unsigned.
You can define the display length (M) and the number of decimals (D). This is
not required and will default to 16,4, where 4 is the number of decimals.
Decimal precision can go to 53 places for a DOUBLE. REAL is a synonym for
DOUBLE.
DECIMAL(M,D) - An unpacked floating-point number that cannot be unsigned. In
unpacked decimals, each decimal corresponds to one byte. Defining the display
length (M) and the number of decimals (D) is required. NUMERIC is a synonym for
DECIMAL.
Date and Time Types:
DATE - A date in YYYY-MM-DD format, between 1000-01-01 and 9999-12-31. For
example, December 30th, 1973 would be stored as 1973-12-30.
DATETIME - A date and time combination in YYYY-MM-DD HH:MM:SS format, between
1000-01-01 00:00:00 and 9999-12-31 23:59:59. For example, 3:30 in the afternoon
on December 30th, 1973 would be stored as 1973-12-30 15:30:00.
TIMESTAMP - A timestamp between midnight, January 1, 1970 and sometime in 2037.
This looks like the previous DATETIME format, only without the hyphens between
numbers; 3:30 in the afternoon on December 30th, 1973 would be stored as
19731230153000 ( YYYYMMDDHHMMSS ).
TIME - Stores the time in HH:MM:SS format.
YEAR(M) - Stores a year in 2-digit or 4-digit format. If the length is specified
as 2 (for example YEAR(2)), YEAR can be 1970 to 2069 (70 to 69). If the length
is specified as 4, YEAR can be 1901 to 2155. The default length is 4.
String Types:
CHAR(M) - A fixed-length string between 1 and 255 characters in length (for
example CHAR(5)), right-padded with spaces to the specified length when stored.
Defining a length is not required, but the default is 1.
VARCHAR(M) - A variable-length string between 1 and 255 characters in length;
for example VARCHAR(25). You must define a length when creating a VARCHAR field.
BLOB or TEXT - A field with a maximum length of 65535 characters. BLOBs are
"Binary Large Objects" and are used to store large amounts of binary data, such
as images or other types of files. Fields defined as TEXT also hold large
amounts of data; the difference between the two is that sorts and comparisons on
stored data are case sensitive on BLOBs and are not case sensitive in TEXT
fields. You do not specify a length with BLOB or TEXT.
TINYBLOB or TINYTEXT - A BLOB or TEXT column with a maximum length of 255
characters. You do not specify a length with TINYBLOB or TINYTEXT.
MEDIUMBLOB or MEDIUMTEXT - A BLOB or TEXT column with a maximum length of
16777215 characters. You do not specify a length with MEDIUMBLOB or MEDIUMTEXT.
LONGBLOB or LONGTEXT - A BLOB or TEXT column with a maximum length of 4294967295
characters. You do not specify a length with LONGBLOB or LONGTEXT.
ENUM - An enumeration, which is a fancy term for list. When defining an ENUM,
you are creating a list of items from which the value must be selected (or it
can be NULL). For example, if you wanted your field to contain "A" or "B" or
"C", you would define your ENUM as ENUM ('A', 'B', 'C') and only those values
(or NULL) could ever populate that field.
1.7.3