BTREE索引

GaussDB(DWS) 支持 BTREE索引，但USING BTREE关键字在语句中的位置与MySQL存在差异。DSC工具迁移时会根据GaussDB的特性进行相应适配。

1. 内联BTREE索引

   输入示例

   CREATE TABLE `public`.`test_create_table03` (
   	`DEMAND_ID` INT(11) NOT NULL AUTO_INCREMENT,
   	`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,
   	PRIMARY KEY(`DEMAND_ID`),
   	INDEX THEME_INDEX(THEME) USING BTREE,
       INDEX NAME_INDEX USING BTREE (SEND_NAME(10))
   );

   输出示例

   CREATE TABLE "public"."test_create_table03"
   (
     "demand_id" SERIAL NOT NULL,
     "demand_name" CHAR(100) NOT NULL,
     "theme" VARCHAR(200) DEFAULT NULL,
     "send_id" INTEGER(11) DEFAULT NULL,
     "send_name" CHAR(20) DEFAULT NULL,
     "send_time" TIMESTAMP WITHOUT TIME ZONE DEFAULT NULL,
     "demand_content" TEXT NOT NULL,
     PRIMARY KEY ("demand_id")
   )
     WITH ( ORIENTATION = ROW, COMPRESSION = NO )
     NOCOMPRESS
     DISTRIBUTE BY HASH ("demand_id");
   CREATE INDEX "theme_index" ON "public"."test_create_table03" USING BTREE ("theme");
   CREATE INDEX "name_index" ON "public"."test_create_table03" USING BTREE ("send_name");

2. ALTER TABLE创建BTREE索引

   输入示例

   CREATE TABLE IF NOT EXISTS `public`.`runoob_alter_test`(
       `dataType1` int NOT NULL AUTO_INCREMENT,
       `dataType2` FLOAT(10,2),
       PRIMARY KEY(`dataType1`)
   );
   
   ALTER TABLE runoob_alter_test ADD KEY alterTable_addKey_indexType (dataType1) USING BTREE;

   输出示例

   CREATE TABLE "public"."runoob_alter_test"
   (
     "datatype1" SERIAL NOT NULL,
     "datatype2" FLOAT(10),
     PRIMARY KEY ("datatype1")
   )
     WITH ( ORIENTATION = ROW, COMPRESSION = NO )
     NOCOMPRESS
     DISTRIBUTE BY HASH ("datatype1");
   
   CREATE INDEX "altertable_addkey_indextype" ON "public"."runoob_alter_test" ("datatype1");

3. CREATE INDEX创建BTREE索引

   输入示例

   CREATE TABLE `public`.`test_create_table03` (
   	`DEMAND_ID` INT(11) NOT NULL AUTO_INCREMENT,
   	`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,
   	PRIMARY KEY(`DEMAND_ID`),
       INDEX CON_INDEX(DEMAND_CONTENT(100)) USING HASH ,
       INDEX SEND_INFO_INDEX USING HASH (SEND_ID,SEND_NAME(10),SEND_TIME)
   );
   
   
   CREATE TABLE `public`.`test_index_table05` (
   	`ID` INT(11) NOT NULL AUTO_INCREMENT,
   	`USER_ID` INT(20) NOT NULL,
   	`USER_NAME` CHAR(20) NULL DEFAULT NULL,
   	`DETAIL` VARCHAR(100) NULL DEFAULT NULL,
   	PRIMARY KEY (`ID`)
   );
   CREATE UNIQUE INDEX USER_ID_INDEX USING BTREE ON TEST_INDEX_TABLE05(USER_ID);
   CREATE INDEX USER_NAME_INDEX USING BTREE ON TEST_INDEX_TABLE05(USER_NAME(10));
   CREATE INDEX DETAIL_INDEX ON TEST_INDEX_TABLE05(DETAIL(50)) USING BTREE;
   CREATE INDEX USER_INFO_INDEX USING BTREE ON TEST_INDEX_TABLE05(USER_ID,USER_NAME(10));

   输出示例

   CREATE TABLE "public"."test_index_table05"
   (
     "id" SERIAL NOT NULL,
     "user_id" INTEGER(20) NOT NULL,
     "user_name" CHAR(20) DEFAULT NULL,
     "detail" VARCHAR(100) DEFAULT NULL,
     PRIMARY KEY ("id")
   )
     WITH ( ORIENTATION = ROW, COMPRESSION = NO )
     NOCOMPRESS
     DISTRIBUTE BY HASH ("id");
   CREATE INDEX "user_id_index" ON "public"."test_index_table05" ("user_id");
   CREATE INDEX "user_name_index" ON "public"."test_index_table05" USING BTREE ("user_name");
   CREATE INDEX "detail_index" ON "public"."test_index_table05" USING BTREE ("detail");
   CREATE INDEX "user_info_index" ON "public"."test_index_table05" USING BTREE ("user_id","user_name");