Datatypes

The classes RWDBColumn and RWDBValue have an associated RWDBValue::ValueType that specifies the datatype of the database column or field being referenced. Mapping between this datatype and the database vendor type runs in both directions:

When fetching data or retrieving information about tables, the DB Access Module for MySQL converts the MySQL type value into RWDBValue::ValueTypes. This mapping is shown in Table 219, which also gives the C++ datatype corresponding to the RWDBValue::ValueType.

When creating tables, the DB Access Module for MySQL maps the given RWDBValue::ValueType into a MySQL datatype. This mapping is shown in Table 220.

The RWDBValue::ValueType, accessible through the type() method, is uniform across all Access Modules. For a complete explanation of the DB Interface Module data model, see Chapter 7, "The Data Model," in the DB Interface Module User’s Guide, and RWDBValue in the SourcePro API Reference..

Table 219. Type mapping when retrieving data
MySQL Datatype	RWDBValue::ValueType	C++ Datatype
`decimal, numeric`	`Decimal`	RWDecimalPortable
`bigint`	`UnsignedLongLong, LongLong`	`unsigned long long, long long`
`tinyblob, blob, mediumblob, longblob`	`Blob`	RWDBBlob
`double`	`Double`	`double`
`float`	`Float`	`float`
`tinyint`	`Char, UnsignedChar`	`char, unsigned char`
`smallint`	`Short, UnsignedShort`	`short, unsigned short`
`integer, mediumint`	`Long, UnsignedLong`	`long, unsigned long`
`char, varchar, tinytext, mediumtext, text, longtext, enum, set`	`String`	RWCString
`date`¹	`Date`	RWDate
`datetime`¹ `time`¹ `timestamp`²	`DateTime`	RWDateTime
`year`	`UnsignedShort`	`unsigned short`

Table 220. Type mapping when creating tables
RWDBValue::ValueType	MySQL Datatypes
`Blob`	`MEDIUMBLOB` if length is `RWDB_NO_TRAIT`. If 0<= length <= 255 `TINYBLOB`. If 256 <= length <=65,535 `BLOB`. If 65,536 <= length <= 16,777,215 `MEDIUMBLOB.` Otherwise, `LONGBLOB`.
`Tiny, UnsignedTiny, Char, UnsignedChar`	`TINYINT`
`Date`	`DATE`
`DateTime`	`DATETIME`
`Decimal (p,s)`	`DECIMAL` using precision and scale of column. If p <= 0 defaults to 8. If s <= 0 defaults to 0.
`Double`	`DOUBLE`
`Float (P)`	`FLOAT` if precision is `RWDB_NO_TRAIT`. Otherwise, `FLOAT (p)` using precision of column.
`Int`, `UnsignedInt, Long`, `UnsignedLong`	`INT`
`Short`, `UnsignedShort`	`SMALLINT`
`LongLong, UnsignedLongLong`	`BIGINT`
`String`	`MEDIUMTEXT` if length is `RWDB_NO_TRAIT`. If 0<= length <= 255 `VARCHAR(length)` using the `storageLength` of the RWDBColumn. If 256 <= length <= 65,535 `TEXT`. If 65,536 <= length <= 16,777,215 `MEDIUMTEXT.` Otherwise `LONGTEXT.`

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