This is a document for PGroonga 2.X and 3.X. See PGroonga 1.x document when you're using old PGroonga.
pgroonga_command functionpgroonga_command function executes a Groonga command and returns the result as text type value.
Here is the syntax of this function:
text pgroonga_command(command)
command is a text type value. pgroonga_command executes command as a Groonga command.
Here is another syntax of this function. It can be used since 1.1.9:
text pgroonga_command(name,
ARRAY[argument_name1, argument_value1,
argument_name2, argument_value2,
...])
The second syntax is recommended because it escapes argument values automatically. It prevents syntax error and Groonga command injection.
name is a text type value. It's a command name to be executed.
argument_name is a text type value. It's an argument name followed by the corresponded argument value.
argument_value is a text type value. It's an argument value of the preceding argument name.
pgroonga_command builds a Groonga command from name and argument_names and argument_values and executes the built Groonga command.
Groonga command returns result as JSON. pgroonga_command returns the JSON as text type value. You can use JSON functions and operations provided by PostgreSQL by casting the result to json or jsonb type.
Here are sample schema and data:
CREATE TABLE memos (
content text
);
CREATE INDEX pgroonga_memos_index
ON memos
USING pgroonga (content);
INSERT INTO memos VALUES ('PGroonga (PostgreSQL+Groonga) is great!');
Here is an example to run status Groonga command that doesn't have any arguments:
SELECT jsonb_pretty(pgroonga_command('status')::jsonb);
-- jsonb_pretty
-- -----------------------------------------
-- [ +
-- [ +
-- 0, +
-- 1480484730.607103, +
-- 0.0001363754272460938 +
-- ], +
-- { +
-- "uptime": 859, +
-- "version": "6.1.0-53-g460b5c9",+
-- "n_queries": 6, +
-- "starttime": 1480483871, +
-- "start_time": 1480483871, +
-- "alloc_count": 14034, +
-- "cache_hit_rate": 0.0, +
-- "command_version": 1, +
-- "max_command_version": 3, +
-- "default_command_version": 1 +
-- } +
-- ]
-- (1 row)
Here is an example to search inserted data. You can use select Groonga command for the purpose. You need to convert PGroonga index name to Groonga table name by pgroonga_table_name function.
SELECT jsonb_pretty(
pgroonga_command(
'select ' ||
'--table ' || pgroonga_table_name('pgroonga_memos_index')
)::jsonb
);
-- jsonb_pretty
-- ------------------------------------------------------------
-- [ +
-- [ +
-- 0, +
-- 1480484984.533947, +
-- 0.0005786418914794922 +
-- ], +
-- [ +
-- [ +
-- [ +
-- 1 +
-- ], +
-- [ +
-- [ +
-- "_id", +
-- "UInt32" +
-- ], +
-- [ +
-- "content", +
-- "LongText" +
-- ], +
-- [ +
-- "ctid", +
-- "UInt64" +
-- ] +
-- ], +
-- [ +
-- 1, +
-- "PGroonga (PostgreSQL+Groonga) is great!",+
-- 1 +
-- ] +
-- ] +
-- ] +
-- ]
-- (1 row)
Here is an example that searches records that contains "PostgreSQL" and "Groonga". Note that you need to quote "PostgreSQL Groonga" to treat as one argument value:
SELECT jsonb_pretty(
pgroonga_command(
'select ' ||
'--table ' || pgroonga_table_name('pgroonga_memos_index') || ' ' ||
'--match_columns content ' ||
'--query "PostgreSQL Groonga"'
)::jsonb
);
-- jsonb_pretty
-- ------------------------------------------------------------
-- [ +
-- [ +
-- 0, +
-- 1480485153.923481, +
-- 0.002448797225952148 +
-- ], +
-- [ +
-- [ +
-- [ +
-- 1 +
-- ], +
-- [ +
-- [ +
-- "_id", +
-- "UInt32" +
-- ], +
-- [ +
-- "content", +
-- "LongText" +
-- ], +
-- [ +
-- "ctid", +
-- "UInt64" +
-- ] +
-- ], +
-- [ +
-- 1, +
-- "PGroonga (PostgreSQL+Groonga) is great!",+
-- 1 +
-- ] +
-- ] +
-- ] +
-- ]
-- (1 row)
If you use arguments array style, you don't need to care about quoting:
SELECT jsonb_pretty(
pgroonga_command(
'select',
ARRAY[
'table', pgroonga_table_name('pgroonga_memos_index'),
'match_columns', 'content',
'query', 'PostgreSQL Groonga'
]
)::jsonb
);
-- jsonb_pretty
-- ------------------------------------------------------------
-- [ +
-- [ +
-- 0, +
-- 1480485246.841189, +
-- 0.00008869171142578125 +
-- ], +
-- [ +
-- [ +
-- [ +
-- 1 +
-- ], +
-- [ +
-- [ +
-- "_id", +
-- "UInt32" +
-- ], +
-- [ +
-- "content", +
-- "LongText" +
-- ], +
-- [ +
-- "ctid", +
-- "UInt64" +
-- ] +
-- ], +
-- [ +
-- 1, +
-- "PGroonga (PostgreSQL+Groonga) is great!",+
-- 1 +
-- ] +
-- ] +
-- ] +
-- ]
-- (1 row)
select Groonga commandYou need to take care about invalid tuples when you use select Groonga command.
See pgroonga_tuple_is_alive Groonga function for details.