Description
Reads a record from a native table, assigning the record to the specified variable.
Syntax
Read variable From [table_var | Cursor cursorvar], key Then | Else statements
Parameters
The Read statement has the following parameters.
| Parameter | Description |
|---|---|
| Variable | Assigned the value of the data that is read from the row specified by key. |
| Table_var | A table variable created by a previous Open statement. |
| Cursorvar | If accessing a cursor, cursorvar contains a cursor variable. Cursor variables are initialized with a Select...By statement and must be preceded with the word Cursor. If the table being accessed has had control features added, cursor access will automatically invoke domain conversion during a Read. |
| Key | The row referenced by key will be read from the table identified by table_var or the table accessed using the cursor in cursorvar. |
| Then | The statement(s) following Then are executed if a row key is read successfully. |
| Else | The statement(s) following Else are executed if the row in variable cannot be read. The Status() function indicates the severity of the error, and the system variable @FILE_ERROR contains details about the nature of the error. |
See also
Open, ReadO, ReadV, MatRead, Write
Example
/* The row having key 101 is read into the variable CUST as a dynamic array. */ open "CUSTOMER" To CUSTOMER_TABLE then read CUST From CUSTOMER_TABLE, "101" else status = Set_FSError() return end end /* Select...By initializes a Cursor with a sorted list of customer records. A ReadNext and Read loop reads each record in turn, passing the customer records to a local subroutine (not shown) for processing. Note the use of the Cursor keyword and the Cursorvar. */ CURSOR_NO = "" Select CUSTOMER_TABLE By "ST" Setting CURSOR_NO Else status = Set_FSError() Return end Done = 0 loop ReadNext @ID Using CURSOR_NO else Done = 1 Until Done Do read @RECORD From CUSTOMER_TABLE, @ID then status = Set_FSError() return end * processing logic here ... GoSub PROCESS Repeat
