table index add

This topic describes how to add secondary indexes on HPE Ezmeral Data Fabric Database JSON tables.

Permissions Required

To run this command, your user ID must have the following permissions:

readAce on the volume
lookupdir on directories in the table path
indexperm permission on the table

If you created the table in version 6.0 or later, you automatically have indexperm permission. For tables created before 6.0, even if you are the owner of the table, you must explicitly add indexperm permission.

NOTE

The mapr user is not treated as a superuser. HPE Ezmeral Data Fabric Database does not allow the mapr user to run this command unless that user is given the relevant permission or permissions with access-control expressions.

Syntax

CLI

maprcli table index add
  -path <path>
  -index <index name>
  -indexedfields < indexed field names >
  [ -includedfields < included field names > ]
  [ -hashed [ enable hashed index: true | false> ] 
  [ -numhashpartitions < number of hash index partitions when hashed index is enabled > ]

REST

curl -X POST \
  'http[s]://<host>:<port>/rest/table/index/add?path=<path>&index=<index name>&indexedfields=<indexed field names>&<parameters>' \
  -u <username>:<password>

Parameters

Parameter	Description
path	(Required) Path to where the parent JSON table resides.
index	(Required) Name of the index.
indexedfields	(Required) Names of the indexed fields. This is a comma separated list of the fields from the JSON table that are indexed and used for ordering the index. The sort ordering of each field can be specified separately. The syntax is as follows: `-indexedfields <fieldname>:<sort_order>,<fieldname>:<sort_order>,...` IMPORTANT Do not place a space between the commas and the field names. A sort_order of `asc`, `ASC`, or `1` denotes an ascending sort order. This is the default. A sort _order of `desc`, `DESC`, or `-1` denotes a descending sort order. The following example specifies two indexed fields. `fieldName1` has an ascending sort, while `fieldName2` is descending. `-indexedfields fieldName1:asc,fieldName2:desc` If an indexed field contains a colon (:) in the name, you need to escape the last colon in the name. In the example below, the indexed field names are the following: `field1` `field2` `colonField:X:Y` The following shows how to escape the last colon in the third indexed field. `-indexedfields field1,field2,colonField:X\\:Y` NOTE The CAST function can be applied on indexed fields. You must enclose each CAST function call in single quotes. See the next section for details.
includedfields	(Optional) Names of the included fields. This is a comma separated list of the fields from the JSON table that are part of the index, but not used for ordering. The syntax is as follows: `-includedfields <fieldname>,<fieldname>,...` IMPORTANT Do not place a space between the commas and the included field names.
hashed	(Optional) True \| False. Default: false
numhashpartitions	(Optional) Number of hash index partitions when the hashed index option is enabled. This parameter determines the number of logical partitions HPE Ezmeral Data Fabric Database distributes keys across. Incoming keys are hashed to 2 byte partition IDs. Default: 10

Applying CAST on Indexed Fields

Indexes can be defined with the CAST function applied to an indexed field.

The following statement queries a table named lineitem and casts the L_LINENUMBER and L_ORDERKEY fields to the int data type.

SELECT L_LINESTATUS, L_QUANTITY FROM lineitem WHERE CAST(L_LINENUMBER as int) = 1 AND CAST(L_ORDERKEY as int) = 550;

To optimize the previous statement, you can create an index on the L_LINENUMBER and L_ORDERKEY fields, and use the CAST function to map each field to a specific data type, as shown below:

maprcli table index add \
  -path /drill/testdata/qa/sf1/maprdb/json/lineitem \
  -index l_cast_comp_1 -indexedfields '$CAST(L_LINENUMBER@INT)','$CAST(L_ORDERKEY@INT)' \
  -includedfields L_LINESTATUS,L_QUANTITY

The index stores the values of the L_LINENUMBER and L_ORDERKEY fields as the int data type. HPE Ezmeral Data Fabric Database can use the index for any subsequent queries that cast these fields to int instead of accessing data in the primary table and converting the values to int.

See Using Casts in Secondary Indexes for more information.

Restrictions

The following restrictions apply to creating indexes.

Name Restrictions

You cannot use the following characters in the index name and in the indexed fields:

 < > ? % \

To use the following characters in the index name and in the indexed fields, enclose them either in single or double quotes:

; | ( ) /

For example:

maprcli table index add -path /volume1/MYTABLE -index "MYTABLE1_ANALYSIS_1設備^=#;{}&()/" \
  -indexedfields "日時_timestamp":desc,"設備タイプ","LOTNo" -includedfields \
  "データタイプ","達成度^=#;{}&()/" (or)

maprcli table index add -path /volume1/MYTABLE -index 'MYTABLE1_ANALYSIS_1設備^=#;{}&()/' \
  -indexedfields "日時_timestamp":desc,"設備タイプ","LOTNo" -includedfields \
  'データタイプ','達成度^=#;{}&()/'

To use either the ' or the " character in the index name and in the indexed fields, enclose:

the ' character within double quotes (")
the " character within single quote (')

For example:

maprcli table index add -path /volume1/MYTABLE -index "'MYTABLE1_ANALYSIS_1設備^=#;{}&()/" \
  -indexedfields "日時_timestamp":desc,"設備タ'イプ","LOTNo" -includedfields \
  "データタイプ'","達成度^=#;{}&()/" (or)

maprcli table index add -path /volume1/MYTABLE -index '"MYTABLE1_ANALYSIS_1設備^=#;{}&()/' \
  -indexedfields "'日時_timestamp":desc,"設備タイプ","LOTNo" -includedfields \
  'データタイプ"',"達成度^=#;{}&()/"

Type Restrictions

If a composite index includes the same subfield in multiple indexed fields, the implied types of the subfields must be consistent.
For example, you cannot create an index with the following indexed fields:
```
a.b[].c, a.b.d
```
Although subfield b appears in both indexed fields, in the first, it is an array and in the second, it is a nested document.
See Composite Indexes and Container Field Paths for more details.

Size Restrictions

The maximum size of all indexed fields in an index is 32 KB.
If the collective size exceeds 32 KB, then an insert of the corresponding document results in an encoding error (INDEX_ROW_KEY_ENCODER_ERROR_ENCODING_IS_TOO_LONG).
The maximum number of indexes that you can create on a JSON table is 32.

Field Definition Restrictions

You cannot specify individual array elements as indexed fields.
You cannot specify a table's _id field as an indexed field.
If a field contains an array of nested documents and you want to index on subfields in the nested documents, then you must define the indexed field using a container field path.
You can include a specific field only once as either an indexed or included field, with the following two exceptions:
- The indexed field is a container field path:
```
maprcli table index add -path /people \
   -index phoneNumberIdx \
   -indexedfields Phones[].Number \
   -includedfields Phones[].Number
```
- The field specifies a cast to another type.
  
  You can create an index in which the score field is an indexed field cast as a double type, and score is also an included field. The included field retains the original data type of the score field:
```
maprcli table index add -path /castTable \
   -index castIdx1 \
   -indexedfields '$CAST(score@DOUBLE)' \
   -includedFields score
```
  You can create an index in which the score field is an indexed field, cast as a double type, and the score field is also another indexed field, cast as a long type:
```
maprcli table index add -path /castTable \
   -index castIdx2 \
   -indexedfields '$CAST(score@DOUBLE)','$CAST(score@LONG)'
```
You cannot use casts with included fields.
You cannot specify a field as either an indexed or included field if the field is also specified as a column family JSON path name.
For example, suppose you have the following JSON table:
```
{
     "_id" : "ID",
     "a" :
          {
               "b" : 
                    {
                         "c" : "value",
                         "d" : "value"
                    },
               "e" : "value"
          }
}
```
If you create a column family at field c in the JSON path a.b.c, you cannot define field a.b.c as either an indexed or included field. You can define the fields a, a.b, and a.b.d as either indexed or included fields.

You cannot specify an included field in which the data in the field spans more than one column family.

In the following example, the included field sl1.sl2 spans column families, cf2 and cf3:

maprcli table cf list -path /cftab
compressionperm  readperm  traverseperm  jsonfamilypath   writeperm  minversions  maxversions  compression  ttl         inmemory  cfname   memoryperm
u:root           u:root    u:root                         u:root     0            1            lz4          2147483647  false     default  u:root
u:root           u:root    u:root        sl1              u:root     0            1            lz4          2147483647  false     cf1      u:root
u:root           u:root    u:root        sl1.sl2.sl3      u:root     0            1            lz4          2147483647  false     cf2      u:root
u:root           u:root    u:root        sl1.sl2.sl3.sl4  u:root     0            1            lz4          2147483647  false     cf3      u:root
                                 
maprcli table index add -path /cftab -index i1 -indexedfields sl1.sl2.sl3.sl4.l4a, sl1.l1a -includedfields sl1.sl2,sl1.sl2.sl3.sl4.sl5.l5b -json
{
        "timestamp":1507419777919,
        "timeofday":"2017-10-07 04:42:57.919 GMT-0700 PM",
        "status":"ERROR",
        "errors":[
                {
                        "id":22,
                        "desc":"Data for included field sl1.sl2 may not span more than one column family."
                }
         ]
}

You cannot specify a composite index with more than one container field path as your indexed fields, unless the prefixes of the container field paths are the same.
See Composite Indexes and Container Field Paths for more details.
You cannot specify a composite index with an indexed field that is a subfield of another indexed field.
For example, you cannot create an index with the following indexed fields:
```
a, a.b
```
The indexed field a.b is a subfield of the indexed field a.

Option Restrictions

As indexes are automatically split, you cannot disable splits when you create your index.

Index Use Restrictions

Indexes do not optimize non-existence filter conditions.

Example

CLI

maprcli table index add -path /demo/business -index newIndex -indexedfields fieldName

REST

curl -k -X POST \
  'https://r1n1.sj.us:8443/rest/table/index/add?path=%2Fdemo%2Fbusiness&index=newIndex&indexedfields=fieldName' \
  -u mapr:mapr

HPE Ezmeral Data Fabric – Customer-Managed 7.9.0 Documentation
Abstract	This site contains documentation for the customer-managed platform of the HPE Ezmeral Data Fabric version 7.9.0 including installation, configuration, administration, and reference content, as well as content for the associated bundled ecosystem components and drivers.
Published	November 2024
Edition	7.9.0