CREATE TABLE sales (
    id INT NOT NULL,
    sale_date DATE NOT NULL,
    amount DECIMAL(10,2)
)
PARTITION BY RANGE (YEAR(sale_date)) (
    PARTITION p0 VALUES LESS THAN (2020),
    PARTITION p1 VALUES LESS THAN (2021),
    PARTITION p2 VALUES LESS THAN (2022),
    PARTITION p3 VALUES LESS THAN MAXVALUE
);

CREATE DEFINER=`root`@`%` PROCEDURE `convert_table_to_partition`(IN tbl_name VARCHAR(200),OUT out_status INT)
BEGIN
    DECLARE done INT DEFAULT FALSE;
    -- 輸出狀態(tài)，開始執(zhí)行狀態(tài) 100，執(zhí)行成功狀態(tài) 200，執(zhí)行失敗狀態(tài) 50
    SET out_status = 100;
    
    -- 創(chuàng)建一個(gè)新的空表，不包含表分區(qū)（要轉(zhuǎn)換為分區(qū)表，必須是空表）
    SET @create_empty_tbl_sql = CONCAT(
        'CREATE TABLE ', tbl_name, '_partitioned LIKE ', tbl_name, ';'
    );
    PREPARE stmt FROM @create_empty_tbl_sql;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    -- 獲取所有唯一的 year_no 和 month_no 組合作為構(gòu)建分區(qū)定義分區(qū)鍵
    SET @partition_def = '';
    SET @query = CONCAT(
        'SELECT GROUP_CONCAT(
            CONCAT("PARTITION p_", year_no, "_", LPAD(month_no, 2, "0"), 
                   " VALUES LESS THAN (", 
                   CASE WHEN month_no = 12 THEN year_no + 1 ELSE year_no END, ", ", 
                   CASE WHEN month_no = 12 THEN 1 ELSE month_no + 1 END, ")")
            ORDER BY year_no, month_no SEPARATOR ",\n"
        ) INTO @partition_def
        FROM (
            SELECT DISTINCT year_no, month_no
            FROM ', tbl_name, '
            ORDER BY year_no, month_no
        ) AS unique_years_months;'
    );
    PREPARE stmt FROM @query;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    -- 調(diào)試信息：輸出分區(qū)定義字符串
    --SELECT tbl_name,@partition_def;

    -- 檢查是否有有效的分區(qū)定義
    IF @partition_def IS NULL OR @partition_def = '' THEN
        SELECT tbl_name,'No data found for partitioning. Skipping partition creation and data migration.';
        -- 空表則直接添加 p_max 分區(qū)用于捕獲未來(lái)數(shù)據(jù)
        SET @partition_def = '\nPARTITION p_max VALUES LESS THAN (MAXVALUE, MAXVALUE)';
    ELSE
        -- 添加 p_max 分區(qū)用于捕獲未來(lái)數(shù)據(jù)
        SET @partition_def = CONCAT(@partition_def, ',\nPARTITION p_max VALUES LESS THAN (MAXVALUE, MAXVALUE)');
    END IF;

    -- 使用 ALTER TABLE 添加分區(qū)定義
    SET @add_partitions_sql = CONCAT(
        'ALTER TABLE ', tbl_name, '_partitioned 
        PARTITION BY RANGE COLUMNS(year_no, month_no) (', @partition_def, ');'
    );

    -- 調(diào)試信息：輸出添加分區(qū)的 SQL 語(yǔ)句
    --SELECT tbl_name,@add_partitions_sql;

    PREPARE stmt FROM @add_partitions_sql;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    -- 遷移數(shù)據(jù)到新的分區(qū)表
    SET @insert_into_partitioned_sql = CONCAT(
        'INSERT INTO ', tbl_name, '_partitioned SELECT * FROM ', tbl_name, ';'
    );

    -- 調(diào)試信息：輸出插入數(shù)據(jù)的 SQL 語(yǔ)句
    -- SELECT tbl_name,@insert_into_partitioned_sql;

    PREPARE stmt FROM @insert_into_partitioned_sql;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    -- 驗(yàn)證數(shù)據(jù)遷移是否成功
    SET @count_original = CONCAT('SELECT COUNT(*) INTO @count_original FROM ', tbl_name);
    PREPARE stmt FROM @count_original;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    SET @count_partitioned = CONCAT('SELECT COUNT(*) INTO @count_partitioned FROM ', tbl_name, '_partitioned');
    PREPARE stmt FROM @count_partitioned;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    -- 比較原表和新分區(qū)表的數(shù)據(jù)行數(shù)
    -- SELECT tbl_name,@count_original, @count_partitioned;

    
    -- 如果數(shù)據(jù)遷移成功，刪除舊表并重命名新表（無(wú)論是否有數(shù)據(jù)，均刪除緩存表）
    IF @count_original = @count_partitioned THEN
        -- 刪除舊表
        SET @drop_old_table_sql = CONCAT('DROP TABLE IF EXISTS ', tbl_name);
        PREPARE stmt FROM @drop_old_table_sql;
        EXECUTE stmt;
        DEALLOCATE PREPARE stmt;

        -- 重命名新表為舊表名
        SET @rename_tables_sql = CONCAT('RENAME TABLE ', tbl_name, '_partitioned TO ', tbl_name);
        PREPARE stmt FROM @rename_tables_sql;
        EXECUTE stmt;
        DEALLOCATE PREPARE stmt;

        -- SELECT tbl_name,'Table conversion and data migration completed successfully.';
        SET out_status = 200;
    ELSE
        -- SELECT tbl_name,'Data migration failed, check the logs for more information.';
        SET out_status = 50;
    END IF;
    
END

CREATE DEFINER=`root`@`%` PROCEDURE `tables_convert_to_partition`()
BEGIN
    DECLARE done INT DEFAULT FALSE;
    DECLARE tbl_name VARCHAR(64);
    DECLARE convert_status INT;
    DECLARE cur CURSOR FOR
        SELECT TABLE_NAME
        FROM information_schema.TABLES
        WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME LIKE 'ai_result_%';
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

    OPEN cur;

    read_loop: LOOP
        FETCH cur INTO tbl_name;
        IF done THEN
            LEAVE read_loop;
        END IF;
      
        -- 調(diào)試信息：輸出正在轉(zhuǎn)換的表
        SELECT tbl_name,'covering...';

        CALL convert_table_to_partition(tbl_name,@status);
        
        SET convert_status = @status;
        
        -- 根據(jù)返回的狀態(tài)進(jìn)行相應(yīng)的處理
        CASE convert_status
            WHEN 100 THEN
                -- 開始狀態(tài)，可以忽略，因?yàn)檫@是預(yù)期的初始狀態(tài)
                SELECT tbl_name, 'Started conversion.';
            WHEN 200 THEN
                -- 成功完成
                SELECT tbl_name, 'Conversion and data migration completed successfully.';
            WHEN 50 THEN
                -- 失敗
                SELECT tbl_name, 'Data migration failed. Check the logs for more information.';
            ELSE
                -- 未知狀態(tài)
                SELECT tbl_name, CONCAT('Unknown status: ', status);
        END CASE;
    END LOOP;

    CLOSE cur;
END

CREATE DEFINER=`root`@`%` PROCEDURE `add_monthly_partitions`(IN tbl_name VARCHAR(64), IN year_no INT, IN month_no INT,OUT out_status INT)
BEGIN
    DECLARE done INT DEFAULT FALSE;
    
    -- 輸出狀態(tài)，開始執(zhí)行狀態(tài) 100，執(zhí)行成功狀態(tài) 200，執(zhí)行失敗狀態(tài) 50
    SET out_status = 100;
    
    -- 檢查待添加的分區(qū)是否已經(jīng)存在
    SET @partition_exists = EXISTS (SELECT 1 FROM information_schema.PARTITIONS 
                                    WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = tbl_name 
                                      AND PARTITION_NAME = CONCAT('p_', year_no, '_', LPAD(month_no, 2, '0')));
                                      
    IF @partition_exists THEN
        -- 如果分區(qū)已存在，直接返回消息
        -- SELECT CONCAT('Partition p_', year_no, '_', LPAD(month_no, 2, '0'), ' already exists. No action taken.') AS message;
        SET out_status = 200;
    ELSE
      -- 檢查表中是否已經(jīng)存在 p_max 分區(qū)
      SET @has_p_max = EXISTS (SELECT 1 FROM information_schema.PARTITIONS 
                               WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = tbl_name 
                                 AND PARTITION_NAME = 'p_max');

      -- 構(gòu)建添加分區(qū)的 SQL 語(yǔ)句
      IF @has_p_max THEN
          -- 如果存在 p_max 分區(qū)，則重新組織分區(qū)，將 p_max 分割成新分區(qū)和更新后的 p_max
          SET @reorganize_partition_sql = CONCAT(
              'ALTER TABLE ', tbl_name, ' REORGANIZE PARTITION p_max INTO (
                  PARTITION p_', year_no, '_', LPAD(month_no, 2, '0'), 
                  ' VALUES LESS THAN (', 
                  CASE WHEN month_no = 12 THEN year_no + 1 ELSE year_no END, ', ', 
                  CASE WHEN month_no = 12 THEN 1 ELSE month_no + 1 END, '),
                  PARTITION p_max VALUES LESS THAN (MAXVALUE, MAXVALUE)
              )'
          );
          PREPARE stmt FROM @reorganize_partition_sql;
          EXECUTE stmt;
          DEALLOCATE PREPARE stmt;

          -- SELECT CONCAT('Partition p_', year_no, '_', LPAD(month_no, 2, '0'), ' and updated p_max added successfully.') AS message;
          SET out_status = 200;
      ELSE
          -- 如果不存在 p_max 分區(qū)，則直接添加新分區(qū)
          SET @add_partition_sql = CONCAT(
              'ALTER TABLE ', tbl_name, ' ADD PARTITION (
                  PARTITION p_', year_no, '_', LPAD(month_no, 2, '0'), 
                  ' VALUES LESS THAN (', 
                  CASE WHEN month_no = 12 THEN year_no + 1 ELSE year_no END, ', ', 
                  CASE WHEN month_no = 12 THEN 1 ELSE month_no + 1 END, ')
              )'
          );
          PREPARE stmt FROM @add_partition_sql;
          EXECUTE stmt;
          DEALLOCATE PREPARE stmt;
          
          -- SELECT CONCAT('Partition p_', year_no, '_', LPAD(month_no, 2, '0'), ' added successfully.') AS message;
          SET out_status = 200;
      END IF;
    END IF;
END

CREATE DEFINER=`root`@`%` PROCEDURE `tables_add_monthly_partition`(IN tbl_prefix VARCHAR(64), IN year_no INT, IN month_no INT,OUT out_status INT)
BEGIN
    DECLARE done INT DEFAULT FALSE;
    DECLARE tbl_name VARCHAR(64);
    DECLARE cur CURSOR FOR
        SELECT TABLE_NAME
        FROM information_schema.TABLES
        WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME LIKE CONCAT(tbl_prefix, '%');
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

    -- 輸出狀態(tài)，開始執(zhí)行狀態(tài) 100，執(zhí)行成功狀態(tài) 200，執(zhí)行失敗狀態(tài) 50
    SET out_status = 100;

    -- 打開游標(biāo)
    OPEN cur;

    read_loop: LOOP
        FETCH cur INTO tbl_name;
        IF done THEN
            LEAVE read_loop;
        END IF;

        -- 檢查表是否已經(jīng)是分區(qū)表
        SET @is_partitioned = EXISTS (SELECT 1 FROM information_schema.PARTITIONS 
                                      WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = tbl_name);

        IF NOT @is_partitioned THEN
            -- 如果表不是分區(qū)表，先調(diào)用 convert_table_to_partition 進(jìn)行轉(zhuǎn)換
            CALL convert_table_to_partition(tbl_name,@status);
            
            -- 轉(zhuǎn)換后再次檢查是否成功轉(zhuǎn)換為分區(qū)表
            SET @is_partitioned = EXISTS (SELECT 1 FROM information_schema.PARTITIONS 
                                          WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = tbl_name);
            
            IF NOT @is_partitioned THEN
                -- 如果轉(zhuǎn)換失敗，跳過后續(xù)操作并輸出錯(cuò)誤信息
                SELECT CONCAT('Failed to convert table ', tbl_name, ' to partitioned. Skipping.') AS message;
                SET out_status = 50;
                ITERATE read_loop;
            END IF;
        END IF;

        -- 調(diào)用 add_monthly_partitions 為當(dāng)前表添加分區(qū)
        CALL add_monthly_partitions(tbl_name, year_no, month_no,@status);

        -- 可選：輸出操作結(jié)果（用于調(diào)試）
        -- SELECT CONCAT('Processed table: ', tbl_name) AS status;
    END LOOP;

    -- 關(guān)閉游標(biāo)
    CLOSE cur;

    -- 輸出完成信息
    -- SELECT CONCAT('Batch partition addition completed for tables with prefix "', tbl_prefix, '".') AS message;
    SET out_status = 200;
END