Help Center/ GaussDB(DWS)/ Tool Guide/ DSC/ SQL Syntax Migration Reference/ MySQL Syntax Migrating/ Schema Objects and Data Definition Language (DDL)/ Table (Optional Parameters and Operations)/ IF NOT EXISTS
Updated on 2024-07-19 GMT+08:00
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IF NOT EXISTS

DSC supports the conversion of IF NOT EXISTS, which is reserved during the migration.

Input

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DROP TABLE IF EXISTS `categories`;
CREATE TABLE IF NOT EXISTS `categories`
(
    `CategoryID` tinyint(5) unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
    `CategoryName` varchar(15) CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL DEFAULT '' ,
    `Description` mediumtext CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL ,
    `Picture` varchar(50) CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
    UNIQUE   (`CategoryID`)
)ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=latin1;
DROP TABLE IF EXISTS `categories`;

Output

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DROP TABLE IF EXISTS "public"."categories";
CREATE TABLE IF NOT EXISTS "public"."categories" (
  "categoryid" SMALLSERIAL NOT NULL PRIMARY KEY,
  "categoryname" VARCHAR(60) NOT NULL DEFAULT '',
  "description" TEXT NOT NULL,
  "picture" VARCHAR(200) NOT NULL DEFAULT ''
) WITH (ORIENTATION = ROW, COMPRESSION = NO) NOCOMPRESS DISTRIBUTE BY HASH ("categoryid");
DROP TABLE IF EXISTS "public"."categories";