Help Center/ GaussDB(DWS)/ Tool Guide/ DSC/ MySQL Syntax Migrating/ Table (Optional Parameters and Operations)/ PARTITION BY
Updated on 2024-07-19 GMT+08:00
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PARTITION BY

In MySQL, PARTITION BY is used to create partitioned tables. Currently, GaussDB(DWS) supports only range and list partitions in MySQL.

Hash partitions of PARTITION BY are not supported and deleted during migration. The deletion does not affect the current table functions, but may affect the performance slightly.

PARTITION BY RANGE

Input

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CREATE TABLE IF NOT EXISTS `runoob_tbl_part_test`(
  `runoob_id` INT NOT NULL,
  `runoob_title` VARCHAR(100) NOT NULL,
  `runoob_author` VARCHAR(40) NOT NULL,
  `submission_date` VARCHAR(30)
)ENGINE=InnoDB DEFAULT CHARSET=utf8
PARTITION BY RANGE (`runoob_id`)(
    PARTITION p0 VALUES LESS THAN(100),
    PARTITION p1 VALUES LESS THAN(200),
    PARTITION p2 VALUES LESS THAN(300),
    PARTITION p3 VALUES LESS THAN(400),
    PARTITION p4 VALUES LESS THAN(500),
    PARTITION p5 VALUES LESS THAN (MAXVALUE)
);

ALTER TABLE `runoob_tbl_part_test` ADD PARTITION (PARTITION p6 VALUES LESS THAN (600));

ALTER TABLE `runoob_tbl_part_test` ADD PARTITION (PARTITION p7 VALUES LESS THAN (700),PARTITION p8 VALUES LESS THAN (800));

Output

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CREATE TABLE IF NOT EXISTS "public"."runoob_tbl_part_test" (
  "runoob_id" INTEGER NOT NULL,
  "runoob_title" VARCHAR(400) NOT NULL,
  "runoob_author" VARCHAR(160) NOT NULL,
  "submission_date" VARCHAR(120)
) WITH (ORIENTATION = ROW, COMPRESSION = NO) NOCOMPRESS DISTRIBUTE BY HASH ("runoob_id") PARTITION BY RANGE ("runoob_id") (
  PARTITION p0
  VALUES
    LESS THAN (100),
    PARTITION p1
  VALUES
    LESS THAN (200),
    PARTITION p2
  VALUES
    LESS THAN (300),
    PARTITION p3
  VALUES
    LESS THAN (400),
    PARTITION p4
  VALUES
    LESS THAN (500),
    PARTITION p5
  VALUES
    LESS THAN (MAXVALUE)
);
ALTER TABLE "public"."runoob_tbl_part_test" ADD PARTITION p6 VALUES LESS THAN (600);
ALTER TABLE "public"."runoob_tbl_part_test" ADD PARTITION p7 VALUES LESS THAN (700), ADD PARTITION p8 VALUES LESS THAN (800);

PARTITION BY LIST

Input

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CREATE TABLE IF NOT EXISTS `runoob_tbl_part_test`(
    `runoob_id` INT NOT NULL,
    `runoob_title` VARCHAR(100) NOT NULL,
    `runoob_author` VARCHAR(40) NOT NULL,
    `submission_date` VARCHAR(30),
    PRIMARY KEY (`runoob_id`)
    )ENGINE=InnoDB DEFAULT CHARSET=utf8
    PARTITION BY LIST (runoob_id)(
    PARTITION r0 VALUES IN (1, 5, 9, 13, 17, 21),
    PARTITION r1 VALUES IN (2, 6, 10, 14, 18, 22),
    PARTITION r2 VALUES IN (3, 7, 11, 15, 19, 23),
    PARTITION r3 VALUES IN (4, 8, 12, 16, 20, 24)
    );
ALTER TABLE `runoob_tbl_part_test` ADD PARTITION (PARTITION p5 VALUES IN(30, 40, 50, 60, 70, 80));

Output

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CREATE TABLE IF NOT EXISTS "public"."runoob_tbl_part_test" (
  "runoob_id" INTEGER NOT NULL,
  "runoob_title" VARCHAR(400) NOT NULL,
  "runoob_author" VARCHAR(160) NOT NULL,
  "submission_date" VARCHAR(120),
  PRIMARY KEY ("runoob_id")
) WITH (ORIENTATION = ROW, COMPRESSION = NO) NOCOMPRESS DISTRIBUTE BY HASH ("runoob_id") PARTITION BY LIST (runoob_id) (
  PARTITION r0
  VALUES
    (1, 5, 9, 13, 17, 21),
    PARTITION r1
  VALUES
    (2, 6, 10, 14, 18, 22),
    PARTITION r2
  VALUES
    (3, 7, 11, 15, 19, 23),
    PARTITION r3
  VALUES
    (4, 8, 12, 16, 20, 24)
);
ALTER TABLE "public"."runoob_tbl_part_test" ADD PARTITION p5 VALUES (30, 40, 50, 60, 70, 80);