tSQLColumnInfo

See Also: Declaring Variables, Struct

Purpose

SQLColumnInfo returns the column information for the result set into a array of tSQLColumnInfo structs. If you want to put the results into a grid the column information for example can be used to initialize your grid columns. Always call SQLColumnInfo after a SQLExecute or SQLExecDirect.

Type Declaration

Use tSQLExecutor.pkg

Struct tSQLColumnInfo

    String  sName

    Integer iType

    Integer iSize

    Integer iDigits

    Boolean bNullable

End_Struct

Struct Members

sName

The column name.

iType

The column's SQL data type.

iSize

The data size of the column in the table.

iDigits

The number of digits following the decimal separator.

bNullable

Whether the column is nullabe.

More About Size and Digits

The SQLExecutor uses ODBC and returns whatever the SQL Server (or other backend) ODBC driver returns.

In ODBC, the size of a numeric column is the maximum number of digits (before and after the decimal separator) that fit in the column. The digits is the number of decimals. For a Numeric(10.3) the size is 10 and the Digits is 3. A numeric 10.3 can contain 7 before the decimal separator and 3 after. (Note this is the definition in SQL, not in DataFlex !)

Sample:

        CREATE TABLE [dbo].[TestBigNumberTable](

          [ID] [int] NOT NULL,

          [Numeric25_0_Column] [numeric](25, 0) NOT NULL,

          [Numeric16_16_Column] [numeric](32, 16) NOT NULL,

          [Numeric18_16_Column] [numeric](34, 16) NOT NULL,

SQLExecutor returns this in tSQLColumnInfo as:

    SQLColumnInfo: ResultSet: 0 Column: 0, sName=ID, iType=4, iSize=10, , iDigits=0

    SQLColumnInfo: ResultSet: 0 Column: 1, sName=Numeric25_0_Column, iType=2, iSize=25, , iDigits=0

    SQLColumnInfo: ResultSet: 0 Column: 2, sName=Numeric16_16_Column, iType=2, iSize=32, , iDigits=16

    SQLColumnInfo: ResultSet: 0 Column: 3, sName=Numeric18_16_Column, iType=2, iSize=34, , iDigits=16

Syntax

Use tSQLExecutor.pkg

:

tSQLColumnInfo {variableName}

Declaring variables

To declare tSQLColumnInfo  variables, use the name of the type (tSQLColumnInfo) followed by the variable name.

tSQLColumnInfo MySQLColumnInfo

See struct variables for more details of instantiating struct types.