Oracle Cursor: Loop Table Data in SQL

To cycle through table data, you can use a cursor to iterate through each row of the table. Here is an example of using a cursor to cycle through table data:

  1. Declare a cursor variable to store the query results.
DECLARE
  CURSOR c_table_data IS
    SELECT * FROM 表名;
  -- 替换“表名”为实际的表名
  1. Declare a variable to store the single data row returned by the cursor.
  v_data 表名%ROWTYPE;
  -- 替换“表名”为实际的表名
  1. Open the cursor.
BEGIN
  OPEN c_table_data;
  1. Iterate through the data rows returned by the cursor until there is no more data.
  LOOP
    FETCH c_table_data INTO v_data;
    EXIT WHEN c_table_data%NOTFOUND;
    -- 在此处处理数据行,例如输出或操作数据
    ...
  END LOOP;
  1. Close the cursor.
  CLOSE c_table_data;
END;

By processing data rows within a loop, you can perform any operation you desire, such as outputting data, updating data, or executing other logic. Please note that the code block in the example above is for demonstration purposes only, and you will need to modify and expand it based on your actual requirements.

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