更新时间:2024-12-10 GMT+08:00
删除索引
MySQL支持DROP INDEX和ALTER TABLE DROP INDEX两种删除索引的语句。DSC工具迁移时会根据GaussDB(DWS)的特性进行相应适配。
- DROP INDEX
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CREATE TABLE `test_create_table03` ( `DEMAND_ID` INT(11) NOT NULL, `DEMAND_NAME` CHAR(100) NOT NULL, `THEME` VARCHAR(200) NULL DEFAULT NULL, `SEND_ID` INT(11) NULL DEFAULT NULL, `SEND_NAME` CHAR(20) NULL DEFAULT NULL, `SEND_TIME` DATETIME NULL DEFAULT NULL, `DEMAND_CONTENT` TEXT NOT NULL ) COLLATE='utf8_general_ci' ENGINE=InnoDB; CREATE UNIQUE INDEX DEMAND_NAME_INDEX ON TEST_CREATE_TABLE03(DEMAND_NAME); DROP INDEX DEMAND_NAME_INDEX ON TEST_CREATE_TABLE03; CREATE INDEX SEND_ID_INDEX ON TEST_CREATE_TABLE03(SEND_ID); DROP INDEX SEND_ID_INDEX ON TEST_CREATE_TABLE03;
输出示例
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CREATE TABLE "public"."test_create_table03" ( "demand_id" INTEGER NOT NULL, "demand_name" CHAR(400) NOT NULL, "theme" VARCHAR(800) DEFAULT NULL, "send_id" INTEGER DEFAULT NULL, "send_name" CHAR(80) DEFAULT NULL, "send_time" TIMESTAMP WITHOUT TIME ZONE DEFAULT NULL, "demand_content" TEXT NOT NULL ) WITH ( ORIENTATION = ROW, COMPRESSION = NO ) NOCOMPRESS DISTRIBUTE BY HASH ("demand_id"); CREATE INDEX "demand_name_index" ON "public"."test_create_table03" ("demand_name"); DROP INDEX "public"."demand_name_index" RESTRICT; CREATE INDEX "send_id_index" ON "public"."test_create_table03" USING BTREE ("send_id"); DROP INDEX "public"."send_id_index" RESTRICT;
- ALTER TABLE DROP INDEX
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CREATE TABLE `test_create_table03` ( `DEMAND_ID` INT(11) NOT NULL, `DEMAND_NAME` CHAR(100) NOT NULL, `THEME` VARCHAR(200) NULL DEFAULT NULL, `SEND_ID` INT(11) NULL DEFAULT NULL, `SEND_NAME` CHAR(20) NULL DEFAULT NULL, `SEND_TIME` DATETIME NULL DEFAULT NULL, `DEMAND_CONTENT` TEXT NOT NULL ) COLLATE='utf8_general_ci' ENGINE=InnoDB; ALTER TABLE TEST_CREATE_TABLE03 ADD UNIQUE INDEX TEST_CREATE_TABLE03_NAME_INDEX(DEMAND_NAME(50)); ALTER TABLE TEST_CREATE_TABLE03 DROP INDEX TEST_CREATE_TABLE03_NAME_INDEX;
输出示例
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CREATE TABLE "public"."test_create_table03" ( "demand_id" INTEGER NOT NULL, "demand_name" CHAR(400) NOT NULL, "theme" VARCHAR(800) DEFAULT NULL, "send_id" INTEGER DEFAULT NULL, "send_name" CHAR(80) DEFAULT NULL, "send_time" TIMESTAMP WITHOUT TIME ZONE DEFAULT NULL, "demand_content" TEXT NOT NULL ) WITH ( ORIENTATION = ROW, COMPRESSION = NO ) NOCOMPRESS DISTRIBUTE BY HASH ("demand_id"); CREATE INDEX "test_create_table03_name_index" ON "public"."test_create_table03" ("demand_name"); DROP INDEX "public"."test_create_table03_name_index" RESTRICT;
父主题: 索引