Help Center/ Data Warehouse Service / Tool Guide/ DSC/ MySQL Syntax Migrating/ Table (Optional Parameters and Operations)/ PACK_KEYS
Updated on 2025-04-10 GMT+08:00
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PACK_KEYS

In MySQL, PACK_KEYS specifies the index compression mode in the MyISAM storage engine. GaussDB(DWS) does not support this attribute, which will be deleted by DSC during migration.

Input

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CREATE TABLE `public`.`runoob_alter_test`(
    `dataType1` int NOT NULL AUTO_INCREMENT,
    `dataType2` DOUBLE(20,8),
    `dataType3` TEXT NOT NULL,
    PRIMARY KEY(`dataType1`)
) ENGINE=MyISAM PACK_KEYS=1;

##A
ALTER TABLE runoob_alter_test PACK_KEYS 0;
ALTER TABLE runoob_alter_test PACK_KEYS=0;

##B
ALTER TABLE runoob_alter_test PACK_KEYS 1;
ALTER TABLE runoob_alter_test PACK_KEYS=1;

##C
ALTER TABLE runoob_alter_test PACK_KEYS DEFAULT;
ALTER TABLE runoob_alter_test PACK_KEYS=DEFAULT;

Output

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CREATE TABLE "public"."runoob_alter_test"
(
  "datatype1" SERIAL NOT NULL,
  
  "datatype2" DOUBLE PRECISION,
  "datatype3" TEXT NOT NULL,
  PRIMARY KEY ("datatype1")
)
  WITH ( ORIENTATION = ROW, COMPRESSION = NO )
  NOCOMPRESS
  DISTRIBUTE BY HASH ("datatype1");

--A

--B

--C