How in H2DB get sql dump like in MySql?

Yes, there are multiple solutions. One is to run the SCRIPT SQL statement:

SCRIPT TO 'fileName'

Another is to use the Script tool:

java org.h2.tools.Script -url <url> -user <user> -password <password>

Then, there are also the RUNSCRIPT statement and RunScript tool.

By the way, you should consider upgrading to a more recent version of H2. With newer versions, the two files .data.db and .index.db are combined in to a .h2.db file.

If you want to get schema and data, you can use

SCRIPT TO 'dump.sql';

If you want to get only schema, you can use

SCRIPT SIMPLE TO 'dump.txt';

Your shortcut:

$ lsfoo.mv.db$ wget -O h2.jar https://search.maven.org/remotecontent?filepath=com/h2database/h2/1.4.200/h2-1.4.200.jar$ lsfoo.mv.dbh2.jar$ java -cp h2.jar org.h2.tools.Script -url "jdbc:h2:file:./foo" -user sa -password ""$ lsbackup.sqlfoo.mv.dbh2.jar$ cat backup.sql | head -n 20;CREATE USER IF NOT EXISTS "SA" SALT 'bbe17...redacted...' HASH 'a24b84f1fe898...redacted...' ADMIN;CREATE SEQUENCE "PUBLIC"."HIBERNATE_SEQUENCE" START WITH 145;CREATE CACHED TABLE "PUBLIC"."...redacted..."(    "ID" INTEGER NOT NULL SELECTIVITY 100,    [...redacted...]    "...redacted..." VARCHAR(255) SELECTIVITY 100);ALTER TABLE "PUBLIC"."...redacted..." ADD CONSTRAINT "PUBLIC"."CONSTRAINT_8" PRIMARY KEY("ID");-- 102 +/- SELECT COUNT(*) FROM PUBLIC.[...redacted...];INSERT INTO "PUBLIC"."...redacted..." VALUES([...redacted...]),