DELIMITER $$

CREATE PROCEDURE `partition_create`(SCHEMANAME varchar(64), TABLENAME varchar(64), PARTITIONNAME varchar(64), CLOCK int)

BEGIN

        /*

           SCHEMANAME = The DB schema in which to make changes

           TABLENAME = The table with partitions to potentially delete

           PARTITIONNAME = The name of the partition to create

        */

        /*

           Verify that the partition does not already exist

        */

        DECLARE RETROWS INT;

        SELECT COUNT(1) INTO RETROWS

        FROM information_schema.partitions

        WHERE table_schema = SCHEMANAME AND table_name = TABLENAME AND partition_description >= CLOCK;

        IF RETROWS = 0 THEN

        /*

           1. Print a message indicating that a partition was created.

           2. Create the SQL to create the partition.

           3. Execute the SQL from #2.

        */

        SELECT CONCAT( "partition_create(", SCHEMANAME, ",", TABLENAME, ",", PARTITIONNAME, ",", CLOCK, ")" ) AS msg;

        SET @sql = CONCAT( 'ALTER TABLE ', SCHEMANAME, '.', TABLENAME, ' ADD PARTITION (PARTITION ', PARTITIONNAME, ' VALUES LESS THAN (', CLOCK, '));' );

        PREPARE STMT FROM @sql;

        EXECUTE STMT;

        DEALLOCATE PREPARE STMT;

        END IF;

END$$

DELIMITER ;

DELIMITER $$

CREATE PROCEDURE `partition_drop`(SCHEMANAME VARCHAR(64), TABLENAME VARCHAR(64), DELETE_BELOW_PARTITION_DATE BIGINT)

BEGIN

        /*

           SCHEMANAME = The DB schema in which to make changes

           TABLENAME = The table with partitions to potentially delete

           DELETE_BELOW_PARTITION_DATE = Delete any partitions with names that are dates older than this one (yyyy-mm-dd)

        */

        DECLARE done INT DEFAULT FALSE;

        DECLARE drop_part_name VARCHAR(16);

        /*

           Get a list of all the partitions that are older than the date

           in DELETE_BELOW_PARTITION_DATE.  All partitions are prefixed with

           a "p", so use SUBSTRING TO get rid of that character.

        */

        DECLARE myCursor CURSOR FOR

        SELECT partition_name

        FROM information_schema.partitions

        WHERE table_schema = SCHEMANAME AND table_name = TABLENAME AND CAST(SUBSTRING(partition_name FROM 2) AS UNSIGNED) < DELETE_BELOW_PARTITION_DATE;

        DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

        /*

           Create the basics for when we need to drop the partition.  Also, create

           @drop_partitions to hold a comma-delimited list of all partitions that

           should be deleted.

        */

        SET @alter_header = CONCAT("ALTER TABLE ", SCHEMANAME, ".", TABLENAME, " DROP PARTITION ");

        SET @drop_partitions = "";

        /*

           Start looping through all the partitions that are too old.

        */

        OPEN myCursor;

        read_loop: LOOP

        FETCH myCursor INTO drop_part_name;

        IF done THEN

    LEAVE read_loop;

        END IF;

        SET @drop_partitions = IF(@drop_partitions = "", drop_part_name, CONCAT(@drop_partitions, ",", drop_part_name));

        END LOOP;

        IF @drop_partitions != "" THEN

        /*

           1. Build the SQL to drop all the necessary partitions.

           2. Run the SQL to drop the partitions.

           3. Print out the table partitions that were deleted.

        */

        SET @full_sql = CONCAT(@alter_header, @drop_partitions, ";");

        PREPARE STMT FROM @full_sql;

        EXECUTE STMT;

        DEALLOCATE PREPARE STMT;

        SELECT CONCAT(SCHEMANAME, ".", TABLENAME) AS `table`, @drop_partitions AS `partitions_deleted`;

        ELSE

        /*

           No partitions are being deleted, so print out "N/A" (Not applicable) to indicate

           that no changes were made.

        */

        SELECT CONCAT(SCHEMANAME, ".", TABLENAME) AS `table`, "N/A" AS `partitions_deleted`;

        END IF;

END$$

DELIMITER ;

DELIMITER $$

CREATE PROCEDURE `partition_maintenance`(SCHEMA_NAME VARCHAR(32), TABLE_NAME VARCHAR(32), KEEP_DATA_DAYS INT, HOURLY_INTERVAL INT, CREATE_NEXT_INTERVALS INT)

BEGIN

        DECLARE OLDER_THAN_PARTITION_DATE VARCHAR(16);

        DECLARE PARTITION_NAME VARCHAR(16);

        DECLARE OLD_PARTITION_NAME VARCHAR(16);

        DECLARE LESS_THAN_TIMESTAMP INT;

        DECLARE CUR_TIME INT;

        CALL partition_verify(SCHEMA_NAME, TABLE_NAME, HOURLY_INTERVAL);

        SET CUR_TIME = UNIX_TIMESTAMP(DATE_FORMAT(NOW(), '%Y-%m-%d 00:00:00'));

        SET @__interval = 1;

        create_loop: LOOP

        IF @__interval > CREATE_NEXT_INTERVALS THEN

    LEAVE create_loop;

        END IF;

        SET LESS_THAN_TIMESTAMP = CUR_TIME + (HOURLY_INTERVAL * @__interval * 3600);

        SET PARTITION_NAME = FROM_UNIXTIME(CUR_TIME + HOURLY_INTERVAL * (@__interval - 1) * 3600, 'p%Y%m%d%H00');

        IF(PARTITION_NAME != OLD_PARTITION_NAME) THEN

    CALL partition_create(SCHEMA_NAME, TABLE_NAME, PARTITION_NAME, LESS_THAN_TIMESTAMP);

        END IF;

        SET @__interval=@__interval+1;

        SET OLD_PARTITION_NAME = PARTITION_NAME;

        END LOOP;

        SET OLDER_THAN_PARTITION_DATE=DATE_FORMAT(DATE_SUB(NOW(), INTERVAL KEEP_DATA_DAYS DAY), '%Y%m%d0000');

        CALL partition_drop(SCHEMA_NAME, TABLE_NAME, OLDER_THAN_PARTITION_DATE);

END$$

DELIMITER ;

DELIMITER $$

CREATE PROCEDURE `partition_verify`(SCHEMANAME VARCHAR(64), TABLENAME VARCHAR(64), HOURLYINTERVAL INT(11))

BEGIN

        DECLARE PARTITION_NAME VARCHAR(16);

        DECLARE RETROWS INT(11);

        DECLARE FUTURE_TIMESTAMP TIMESTAMP;

        /*

         * Check if any partitions exist for the given SCHEMANAME.TABLENAME.

         */

        SELECT COUNT(1) INTO RETROWS

        FROM information_schema.partitions

        WHERE table_schema = SCHEMANAME AND table_name = TABLENAME AND partition_name IS NULL;

        /*

         * If partitions do not exist, go ahead and partition the table

         */

        IF RETROWS = 1 THEN

        /*

         * Take the current date at 00:00:00 and add HOURLYINTERVAL to it.  This is the timestamp below which we will store values.

         * We begin partitioning based on the beginning of a day.  This is because we don't want to generate a random partition

         * that won't necessarily fall in line with the desired partition naming (ie: if the hour interval is 24 hours, we could

         * end up creating a partition now named "p201403270600" when all other partitions will be like "p201403280000").

         */

        SET FUTURE_TIMESTAMP = TIMESTAMPADD(HOUR, HOURLYINTERVAL, CONCAT(CURDATE(), " ", '00:00:00'));

        SET PARTITION_NAME = DATE_FORMAT(CURDATE(), 'p%Y%m%d%H00');

        -- Create the partitioning query

        SET @__PARTITION_SQL = CONCAT("ALTER TABLE ", SCHEMANAME, ".", TABLENAME, " PARTITION BY RANGE(`clock`)");

        SET @__PARTITION_SQL = CONCAT(@__PARTITION_SQL, "(PARTITION ", PARTITION_NAME, " VALUES LESS THAN (", UNIX_TIMESTAMP(FUTURE_TIMESTAMP), "));");

        -- Run the partitioning query

        PREPARE STMT FROM @__PARTITION_SQL;

        EXECUTE STMT;

        DEALLOCATE PREPARE STMT;

        END IF;

END$$

DELIMITER ;

DELIMITER $$

CREATE PROCEDURE`partition_maintenance_all`(SCHEMA_NAME VARCHAR(32))

BEGIN

               CALL partition_maintenance(SCHEMA_NAME, 'history', 90, 24, 14);

               CALL partition_maintenance(SCHEMA_NAME, 'history_log', 90, 24, 14);

               CALL partition_maintenance(SCHEMA_NAME, 'history_str', 90, 24, 14);

               CALL partition_maintenance(SCHEMA_NAME, 'history_text', 90, 24, 14);

               CALL partition_maintenance(SCHEMA_NAME, 'history_uint', 90, 24, 14);

               CALL partition_maintenance(SCHEMA_NAME, 'trends', 730, 24, 14);

               CALL partition_maintenance(SCHEMA_NAME, 'trends_uint', 730, 24, 14);

END$$

DELIMITER ;