public void ddl()

in modules/runner/src/integrationTest/java/org/apache/ignite/internal/sql/api/ItSqlAsynchronousApiTest.java [104:228]
102 lines of code
3 McCabe index (conditional complexity)

    public void ddl() throws Exception {
        IgniteSql sql = CLUSTER_NODES.get(0).sql();
        Session ses = sql.createSession();

        // CREATE TABLE
        checkDdl(true, ses, "CREATE TABLE TEST(ID INT PRIMARY KEY, VAL0 INT)");
        checkError(
                TableAlreadyExistsException.class,
                "Table already exists [name=\"PUBLIC\".\"TEST\"]",
                ses,
                "CREATE TABLE TEST(ID INT PRIMARY KEY, VAL0 INT)"
        );
        checkError(
                IgniteException.class,
                "Can't create table with duplicate columns: ID, VAL, VAL",
                ses,
                "CREATE TABLE TEST1(ID INT PRIMARY KEY, VAL INT, VAL INT)"
        );
        checkDdl(false, ses, "CREATE TABLE IF NOT EXISTS TEST(ID INT PRIMARY KEY, VAL VARCHAR)");

        // ADD COLUMN
        checkDdl(true, ses, "ALTER TABLE TEST ADD COLUMN VAL1 VARCHAR");
        checkError(
                TableNotFoundException.class,
                "The table does not exist [name=\"PUBLIC\".\"NOT_EXISTS_TABLE\"]",
                ses,
                "ALTER TABLE NOT_EXISTS_TABLE ADD COLUMN VAL1 VARCHAR"
        );
        checkDdl(false, ses, "ALTER TABLE IF EXISTS NOT_EXISTS_TABLE ADD COLUMN VAL1 VARCHAR");
        checkError(
                ColumnAlreadyExistsException.class,
                "Column already exists [name=\"VAL1\"]",
                ses,
                "ALTER TABLE TEST ADD COLUMN VAL1 INT"
        );

        // CREATE INDEX
        checkDdl(true, ses, "CREATE INDEX TEST_IDX ON TEST(VAL0)");
        checkError(
                IndexAlreadyExistsException.class,
                "Index already exists [name=\"PUBLIC\".\"TEST_IDX\"]",
                ses,
                "CREATE INDEX TEST_IDX ON TEST(VAL1)"
        );
        checkDdl(false, ses, "CREATE INDEX IF NOT EXISTS TEST_IDX ON TEST(VAL1)");

        // TODO: IGNITE-19150 We are waiting for schema synchronization to avoid races to create and destroy indexes
        waitForIndexBuild("TEST", "TEST_IDX");

        checkDdl(true, ses, "DROP INDEX TESt_iDX");
        checkDdl(true, ses, "CREATE INDEX TEST_IDX1 ON TEST(VAL0)");
        checkDdl(true, ses, "CREATE INDEX TEST_IDX2 ON TEST(VAL0)");
        checkDdl(true, ses, "CREATE INDEX TEST_IDX3 ON TEST(ID, VAL0, VAL1)");
        checkError(
                SqlException.class,
                "Can't create index on duplicate columns: VAL0, VAL0",
                ses,
                "CREATE INDEX TEST_IDX4 ON TEST(VAL0, VAL0)"
        );

        checkError(
                SqlException.class,
                "Can`t delete column(s). Column VAL1 is used by indexes [TEST_IDX3].",
                ses,
                "ALTER TABLE TEST DROP COLUMN val1"
        );

        SqlException ex = IgniteTestUtils.cause(assertThrows(Throwable.class,
                () -> await(ses.executeAsync(null, "ALTER TABLE TEST DROP COLUMN (val0, val1)"))), SqlException.class);
        assertNotNull(ex);
        assertEquals(STMT_VALIDATION_ERR, ex.code());

        String msg = ex.getMessage();
        String explainMsg = "Unexpected error message: " + msg;

        assertTrue(msg.contains("Column VAL0 is used by indexes ["), explainMsg);
        assertTrue(msg.contains("TEST_IDX1") && msg.contains("TEST_IDX2") && msg.contains("TEST_IDX3"), explainMsg);
        assertTrue(msg.contains("Column VAL1 is used by indexes [TEST_IDX3]"), explainMsg);

        checkError(
                SqlException.class,
                "Can`t delete column, belongs to primary key: [name=ID]",
                ses,
                "ALTER TABLE TEST DROP COLUMN id"
        );

        // TODO: IGNITE-19150 We are waiting for schema synchronization to avoid races to create and destroy indexes
        waitForIndexBuild("TEST", "TEST_IDX3");
        checkDdl(true, ses, "DROP INDEX TESt_iDX3");

        // DROP COLUMNS
        checkDdl(true, ses, "ALTER TABLE TEST DROP COLUMN VAL1");
        checkError(
                TableNotFoundException.class,
                "The table does not exist [name=\"PUBLIC\".\"NOT_EXISTS_TABLE\"]",
                ses,
                "ALTER TABLE NOT_EXISTS_TABLE DROP COLUMN VAL1"
        );
        checkDdl(false, ses, "ALTER TABLE IF EXISTS NOT_EXISTS_TABLE DROP COLUMN VAL1");
        checkError(
                ColumnNotFoundException.class,
                "Column does not exist [tableName=\"PUBLIC\".\"TEST\", columnName=\"VAL1\"]",
                ses,
                "ALTER TABLE TEST DROP COLUMN VAL1"
        );

        // DROP TABLE
        checkDdl(false, ses, "DROP TABLE IF EXISTS NOT_EXISTS_TABLE");

        checkDdl(true, ses, "DROP TABLE TEST");
        checkError(
                TableNotFoundException.class,
                "The table does not exist [name=\"PUBLIC\".\"TEST\"]",
                ses,
                "DROP TABLE TEST"
        );

        checkDdl(false, ses, "DROP INDEX IF EXISTS TEST_IDX");

        checkError(
                IndexNotFoundException.class,
                "Index does not exist [name=\"PUBLIC\".\"TEST_IDX\"]", ses,
                "DROP INDEX TEST_IDX"
        );
    }