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Using the Get* Methods to Read Column Values

Using the Get* Methods to Read Column Values Before I show you the other Get* methods that read column values, you need to know the standard C# types and the values they support | Using the Get Methods to Read Column Values Before I show you the other Get methods that read column values you need to know the standard C types and the values they support. You need to know these so that you can understand the type compatibilities between C and SQL Server shown later. Table 9.3 shows the standard C types along with the underlying .NET type and the values that can be stored in the C type. Table 9.3 STANDARD C AND .NET TYPES C TYPE .NET TYPE VALUES bool Boolean A Boolean true or false value. byte Byte An 8-bit unsigned integer between 0 and 28 - 1 255 . char Char A 16-bit Unicode character. DateTime DateTime A date and time between 12 00 00 AM January 1 0001 and 11 59 59 PM December 31 9999. decimal Decimal A fixed precision and scale number between approximately -1.0 10-28 and approximately -7.9 1028 with 28 significant figures of precision. double Double A 64-bit floating-point number between approximately -5 10-324 and approximately -1.7 10308 with 15 to 16 significant figures of precision. float Single A 32-bit floating-point number between approximately -1.5 10-45 to approximately -3.4 1038 with 7 significant figures of precision. Guid Guid A 128-bit unsigned integer value 16 bytes that that is unique across all computers and networks. int Int32 A 32-bit signed integer between -231 -2 147 483 648 and 231 - 1 2 147 483 647 . long Int64 A 64-bit signed integer between -263 9 223 372 036 854 775 808 and 263 - 1 9 223 372 036 854 775 807 . sbyte SByte An 8-bit signed integer between -27 -128 and 27 - 1 127 . short Int16 A 16-bit signed integer between -215 -32 768 and 215 - 1 32 767 . string String A variable-length string of 16-bit Unicode characters. Table 9.3 STANDARD C AND .NET TYPES C TYPE .NET TYPE VALUES uint UInt32 A 32-bit unsigned integer between 0 and 232 - 1 4 294 967 295 . ulong UInt64 A 64-bit unsigned integer between 0 and 264 - 1 18 446 744 073 709 551 615 . ushort UInt16 A 16-bit unsigned integer between 0 and 216 - 1 65 535 . .