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Teracli Manual

Create Table

./teracli  create        <table-schema>  [<tablet-delimiter-file>]
./teracli  createbyfile  <schema-file>   [<tablet-delimiter-file>]

  • Table-schema is a string used for describing the table schema. SeePropTree for more details.

  • Table name specification: the first character should be a letter (case insensitive); valid character includes alphanumeric character([a-z] and [A-Z]), digits([0-9]), underscores(_), dashes(-); table name's valid length should be [1, 512].

  • Tera supports pre-sharding while creating table, key range describes in tablet-delimiter-file, while each range ends with '\n'

  • User also can use createbyfile with a schema-file to create a table with complicated schema.

Table Schema Mode

Table's schema includes table name, locality groups properties and column families descriptions, a typical schema describes as follow:

# Tablet splitsize 4096M, mergesize 512M
# There are three locality groups, configure as mem, flash and disk

table_hello <splitsize=4096, mergesize=512> {
    lg_index <storage=flash, blocksize=4> {
        update_flag <maxversions=1>
    },
    lg_props <storage=flash, blocksize=32> {
        level,
        weight
    },
    lg_raw <storage=disk, blocksize=128> {
        data <maxversions=10>
    }
}

If schema does not include locality group information, tera will create default lg in disk type, just like:

table_hello {cf0, cf1, cf2}

KV Schema Mode

Tera supports high performance kv table, its schema can only include table name or add some optional locality groups's properties.

# kv mode
kv_hello  
                                              
# kv mode with lg configuration
kv_hello <storage=flash, splitsize=2048, mergesize=128>

Attributes and meanings

Span Properties Meanings Legal value Unit Default value Others
table splitsize If tablet's size has grown to exceed this value, the tablet is splited in two >=0, when splitsize = 0, disable automatic split MB 512
table mergesize If tablet's size has reduced to this value, the adjacent two tablet is merged in one >=0, when mergesize = 0, disable automatic merge MB 0 splitsize is at least 5 times larger than mergesize
lg storage storage type "disk" / "flash" / "memory" - "disk"
lg blocksize Leveldb's block size >0 KB 4
lg use_memtable_on_leveldb whether enable memory compact strategy "true" / "false" - false
lg sst_size sst's size in level0 >0 MB 8
cf maxversions max number of version keeps in tera >0 - 1
cf ttl time-to-live >=0, ttl=0 means never timeout second 0 if ttl conflicts with minversions, minversions has the last word

Update Schema

./teracli update <tableschema>

Update table syntax is the same as create. Update operation can apply to one or more properties at one time.

Update table schema

  1. When update locality group's properties, user need to disable table
  2. Table and column family's properties support online update.

Usage example

Update table properties:

./teracli update "oops<mergesize=512>"
./teracli update "oops<splitsize=1024,mergesize=128>"

Update locality groups properties:

./teracli update "oops{lg0<sst_size=9>}"

# update table properties, while update lg property
./teracli update "oops<splitsize=512>{lg0<sst_size=9>}"

Update column family properties:

./teracli update "oops{lg0{cf0<ttl=999>}}"

#update table and lg property, while update cf property
./teracli update "oops<splitsize=512>{lg0<sst_size=9>{cf0<ttl=999>}}"

Online add/delete column family:

# add cf1 to lg0, and set ttl = 123
# op means operation, op=add need put in front of other cf's properties
./teracli update "oops{lg0{cf1<op=add,ttl=123>}}"

# delete cf1 from lg0
./teracli update "oops{lg0{cf1<op=del>}}"

Update kv schema

# When update kv schema, user need to disable table
./teracli update "kvtable<splitsize=1024>"

Disable Table

Set table into disable state; disable read and write service:

./teracli disable <tablename>

Enable Table

Set a table into enable state; recovery read and write service:

./teracli enable <tablename>

Drop Table

Delete a disable table, this operation could not rollback:

./teracli drop <tablename>

Show Table

Show single table in formation:

./teracli show  <tablename>
./teracli showx <tablename> // for more details

Show all tables' information:

./teracli show
./teracli showx // for more details

Show Schema

Show table schema, including properties of column family or locality group, etc.

./teracli showschema <tablename>
./teracli showschemax <tablename> // more details

Show Tablet Server

Show single tablet server information as belove:

./teracli showts "example.company.com:7770"
./teracli showtsx "example.company.com:7770"  // more details

Show all tablet servers's information:

./teracli showts
./teracli showtsx // more details

Put Operation

Use put to insert a key into table:

./teracli put <tablename> <rowkey> [<columnfamily:qualifier>] <value>

# In kv mode, columnfamily:qualifier should not be set.
./teracli put <tablename> <rowkey> <value>

For example:

./teracli put mytable rowkey cf0:qu0 value

Put-ttl Operation

put-ttl is the same as put, except that key will be invalid after ttl:

./teracli put-ttl <tablename> <rowkey> [<columnfamily:qualifier>] <value> <ttl(second)>

For example:

# key will be invalid after 20 seconds
./teracli put-ttl mytable rowkey cf0:qu0 value 20

Putif Operation

putif is the same as put, except that putif will fail if key already in table; it works like std::map::insert():

./teracli putif <tablename> <rowkey> [<columnfamily:qualifier>] <value>

Get Operation

Use get to read value from table:

./teracli get <tablename> <rowkey> [<columnfamily:qualifier>]

For example:

./teracli get mytable rowkey cf0:qu0

Scan Operation

Use scan to get a sorted key ranged data from table:

# all the key belonging to [start, end), will be scaned out
./teracli scan <tablename> <startkey> <endkey>

# scan all the versions of qualifier
./teracli scanallv <tablename> <startkey> <endkey>

Delete Operation

Delete a qualifier:

./teracli delete <tablename> <rowkey> [<columnfamily:qualifier>]

# delete the newest version of the qualifier
./teracli delete1v <tablename> <rowkey> [<columnfamily:qualifier>]

Support Int64

Tera support setting qualifier's type into int64, use putint64 for initializtion:

# set cell of cf0:qu0 to be 67
./teracli putint64 mytable row1 cf0:qu0 67

Use getint64 to read counter from cell:

./teracli getint64 mytable row1 cf0:qu0

Use addint64 to increase value of cell; the value can be positive or negative:

# add -3 into cell
./teracli addint64 mytable row1 cf0:qu0 -3

Atomic Counter

Tera supports distributed atomic counter, use put_counter to set a counter:

./teracli put_counter <tablename> <rowkey> [<columnfamily:qualifier>] <integer(int64_t)>

For example:

./teracli put_counter mytable rowkey cf0:qu0 3

Use get_counter to read counter from cell:

./teracli get_counter <tablename> <rowkey> [<columnfamily:qualifier>]

For example:

./teracli get_counter mytable rowkey cf0:qu0

Use add to increase counter's value:

./teracli add <tablename> <rowkey> <columnfamily:qualifier> delta

For example, set counter=3 and add 2 on it, then counter will be 5:

./teracli add mytable rowkey cf0:qu0 2

Note：User should apply put_counter, get_counter, or add operations to atomic counter, while use putint64, getint64, addint64 to operate int64 counter. Both of these two counters cannot be confused.

Append Operation

Append operation's syntax describe as follow, it works like std::string::append():

./teracli append <tablename> <rowkey> [<columnfamily:qualifier>] <value>

For example:

# before append, rowkey:cf0:qu0 = 'hello'
./teracli put    mytalbe rowkey cf0:qu0 hello

# exec append
./teracli append mytable rowkey cf0:qu0 world

# after append, rowkey:cf0:qu0 = 'helloworld'
./teracli get mytable rowkey cf0:qu0