get

Encapsulates commands that get key/value pairs from store or get rows from table. The subcommands are as follows:

get kv 

get kv [-key <keyString>] [-file <output>] [-all] [-keyonly]
[-valueonly] [-start <prefixString>] [-end <prefixString>]

Perform a simple get operation using the specified key. The obtained value is printed out if it contains displayable characters, otherwise the bytes array is encoded using Base64 for display purposes. "[Base64]" is appended to indicate this transformation. The arguments for the get command are:

  • -key <keyString>

    Indicates the full or the prefix key path to use. If <keyString> is a full key path, it returns a single value information. The format of this get command is: get -key <keyString>. If <keyString> is a prefix key path, it returns multiple key/value pairs. The format of this get command is: get -key <keyString> -all. Key can be composed of both major and minor key paths, or a major key path only. The <keyString> format is: "major-key-path/-/minor-key-path". Additionally, in the case of the prefix key path, a key can be composed of the prefix part of a major key path.

    For example, with some sample keys in the KVStore: 

    /group/TC/-/user/bob
/group/TC/-/user/john
/group/TC/-/dep/IT
/group/SZ/-/user/steve
/group/SZ/-/user/diana

    A get command with a key containing only the prefix part of the major key path results in: 

    kv -> get kv -key /group -all -keyonly
/group/TC/-/user/bob
/group/TC/-/user/john
/group/TC/-/dep/IT
/group/SZ/-/user/steve
/group/SZ/-/user/diana

    A get command with a key containing a major key path results in: 

    kv -> get kv -key /group/TC -all -keyonly
/group/TC/-/user/bob
/group/TC/-/user/john
/group/TC/-/dep/IT

    Get commands with a key containing major and minor key paths results in: 

    kv -> get kv -key /group/TC/-/user -all -keyonly
/group/TC/-/user/bob
/group/TC/-/user/john
kv -> get kv -key /group/TC/-/user/bob
{
    "name"  : "bob.smith",
    "age"   : 20,
    "email" : "bob.smith@example.com",
    "phone" : "408 555 5555"
}

  • -file <output>

    Specifies an output file, which is truncated, replacing all existing content with new content.

    In the following example, records from the key /Smith/Bob are written to the file "data.out". 

    kv -> get kv -key /Smith/Bob -all -file ./data.out

    In the following example, contents of the file "data.out" are replaced with records from the key /Wong/Bill. 

    kv -> get kv -key /Wong/Bill -all -file ./data.out

  • -all

    Specified for iteration starting at the specified key. If the key argument is not specified, the entire store will be iterated.

  • -keyonly

    Specified with -all to return only keys.

  • -valueonly

    Specified with -all to return only values.

  • -start <prefixString> and -end <prefixString>

    Restricts the range used for iteration. This is particularly helpful when getting a range of records based on a key component, such as a well-formatted string. Both the -start and -end arguments are inclusive.

    Note:

    -start and -end only work on the key component specified by -key <keyString>. The value of <keyString> should be composed of simple strings and cannot have multiple key components specified.

    For example, a log where its key structure is: 

    /log/<year>/<month>/-/<day>/<time>

    puts all log entries for the same day in the same partition, but splits the days across shards. The time format is: "hour.minute".

    In this way, you can do a get of all log entries in February and March, 2013 by specifying: 

    kv-> get kv -all -keyonly -key /log/2013 -start 02 -end 03
/log/2013/02/-/01/1.45
/log/2013/02/-/05/3.15
/log/2013/02/-/15/10.15
/log/2013/02/-/20/6.30
/log/2013/02/-/28/8.10
/log/2013/03/-/01/11.13
/log/2013/03/-/15/2.28
/log/2013/03/-/22/4.52
/log/2013/03/-/31/11.55

    You can be more specific to the get command by specifying a more complete key path. For example, to display all log entries from April 1st to April 4th: 

    kv-> get kv -all -keyonly -key /log/2013/04 -start 01 -end 04
/log/2013/04/-/01/1.03
/log/2013/04/-/01/4.05
/log/2013/04/-/02/7.22
/log/2013/04/-/02/9.40
/log/2013/04/-/03/4.15
/log/2013/04/-/03/6.30
/log/2013/04/-/03/10.25
/log/2013/04/-/04/4.10
/log/2013/04/-/04/8.35

See the subcommand get table

get table

kv-> get table -name <table_name> [-index <name>]
    [-field <name> -value <value>]+
    [-field <name> [-start <value>] [-end <value>]]
    [-ancestor <name>]+ [-child <name>]+
    [-json <string>] [-file <output>] [-keyonly]
    [-pretty] [-report-size]

Identifies a table name, which can be any of the following:

  • -name

    Identifies any of the following tables:

    • table_name – The target table is a top level table created in the default namespace, sysdefault. The default namespace (sysdefault:) prefix is not required to identify such tables.
    • table_name.child_name – The target table is the child of a parent table. Identify the child table by preceding it with the parent table_name, followed by a period (.) separator before child_name.
    • namespace_name:table_name – The target table was not created in the default (sysdefault) namespace. Identify table_name by preceding it with its namespace_name, followed by a colon (:).
    • namespace_name:table_name.child_name – The target table is the child of a parent table that was created in a namespace. Identify child_name by preceding it with both namespace_name: and the parent table_name, , followed by a period (.) separator.

    -field and -value pairs are used to specify the field values of the primary key or index key if using an index, specified by -index, or with an empty key to iterate the entire table.

  • -field flag, along with its -start and -end flags, can be used to define a value range for the last field specified.

  • -ancestor and -child flags are used to return results from specific ancestor and/or descendant tables as well as the target table.

  • -json indicates that the key field values are in JSON format.

  • -file is used to specify an output file, which is truncated.

  • -keyonly is used to restrict information to keys only.

  • -pretty is used for a nicely formatted JSON string with indentation and carriage returns.

  • -report-size is used to show key and data size information for primary keys, data values, and index keys for matching records. When -report-size is specified no data is displayed.