21.4.11 ndb_drop_index — Drop Index from an NDB Table

ndb_drop_index drops the specified index from an NDB table. It is recommended that you use this utility only as an example for writing NDB API applications—see the Warning later in this section for details.

Usage

ndb_drop_index -c connection_string table_name index -d db_name

The statement shown above drops the index named index from the table in the database.

The following table includes options that are specific to ndb_drop_index. Additional descriptions follow the table. For options common to most NDB Cluster programs (including ndb_drop_index), see Section 21.4.32, “Options Common to NDB Cluster Programs — Options Common to NDB Cluster Programs”.

Table 21.247 Command-line options for the ndb_drop_index program

Format Description Added, Deprecated, or Removed

--database=dbname,

-d

Name of database in which table is found

(Supported in all MySQL 5.7 based releases)


Warning

Operations performed on Cluster table indexes using the NDB API are not visible to MySQL and make the table unusable by a MySQL server. If you use this program to drop an index, then try to access the table from an SQL node, an error results, as shown here:

shell> ./ndb_drop_index -c localhost dogs ix -d ctest1
Dropping index dogs/idx...OK

NDBT_ProgramExit: 0 - OK

shell> ./mysql -u jon -p ctest1
Enter password: *******
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7 to server version: 5.7.31-ndb-7.5.20

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW TABLES;
+------------------+
| Tables_in_ctest1 |
+------------------+
| a                |
| bt1              |
| bt2              |
| dogs             |
| employees        |
| fish             |
+------------------+
6 rows in set (0.00 sec)

mysql> SELECT * FROM dogs;
ERROR 1296 (HY000): Got error 4243 'Index not found' from NDBCLUSTER

In such a case, your only option for making the table available to MySQL again is to drop the table and re-create it. You can use either the SQL statementDROP TABLE or the ndb_drop_table utility (see Section 21.4.12, “ndb_drop_table — Drop an NDB Table”) to drop the table.


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