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.. _python_api:
================================
sqlite-utils command-line tool
================================
The `` sqlite-utils `` command-line tool can be used to manipulate SQLite databases in a number of different ways.
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.. _cli_query_json:
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Running queries and returning JSON
==================================
You can execute a SQL query against a database and get the results back as JSON like this::
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$ sqlite-utils query dogs.db "select * from dogs"
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[{"id": 1, "age": 4, "name": "Cleo"},
{"id": 2, "age": 2, "name": "Pancakes"}]
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This is the default subcommand for `` sqlite-utils `` , so you can instead use this::
$ sqlite-utils dogs.db "select * from dogs"
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Use `` --nl `` to get back newline-delimited JSON objects::
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$ sqlite-utils dogs.db "select * from dogs" --nl
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{"id": 1, "age": 4, "name": "Cleo"}
{"id": 2, "age": 2, "name": "Pancakes"}
You can use `` --arrays `` to request ararys instead of objects::
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$ sqlite-utils dogs.db "select * from dogs" --arrays
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[[1, 4, "Cleo"],
[2, 2, "Pancakes"]]
You can also combine `` --arrays `` and `` --nl `` ::
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$ sqlite-utils dogs.db "select * from dogs" --arrays --nl
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[1, 4, "Cleo"]
[2, 2, "Pancakes"]
If you want to pretty-print the output further, you can pipe it through `` python -mjson.tool `` ::
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$ sqlite-utils dogs.db "select * from dogs" | python -mjson.tool
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[
{
"id": 1,
"age": 4,
"name": "Cleo"
},
{
"id": 2,
"age": 2,
"name": "Pancakes"
}
]
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.. _cli_query_csv:
Running queries and returning CSV
=================================
You can use the `` --csv `` option to return results as CSV::
$ sqlite-utils dogs.db "select * from dogs" --csv
id,age,name
1,4,Cleo
2,2,Pancakes
This will default to including the column names as a header row. To exclude the headers, use `` --no-headers `` ::
$ sqlite-utils dogs.db "select * from dogs" --csv --no-headers
1,4,Cleo
2,2,Pancakes
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.. _cli_rows:
Returning all rows in a table
=============================
You can return every row in a specified table using the `` rows `` subcommand::
$ sqlite-utils rows dogs.db dogs
[{"id": 1, "age": 4, "name": "Cleo"},
{"id": 2, "age": 2, "name": "Pancakes"}]
This command accepts the same output options as `` query `` - so you can pass `` --nl `` , `` --csv `` and `` --no-headers `` .
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.. _cli_tables:
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Listing tables
==============
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You can list the names of tables in a database using the `` tables `` subcommand::
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$ sqlite-utils tables mydb.db
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[{"table": "dogs"},
{"table": "cats"},
{"table": "chickens"}]
You can output this list in CSV using the `` -csv `` option::
$ sqlite-utils tables mydb.db --csv --no-headers
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dogs
cats
chickens
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If you just want to see the FTS4 tables, you can use `` --fts4 `` (or `` --fts5 `` for FTS5 tables)::
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$ sqlite-utils tables docs.db --fts4
[{"table": "docs_fts"}]
Use `` --counts `` to include a count of the number of rows in each table::
$ sqlite-utils tables mydb.db --counts
[{"table": "dogs", "count": 12},
{"table": "cats", "count": 332},
{"table": "chickens", "count": 9}]
Use `` --columns `` to include a list of columns in each table::
$ sqlite-utils tables dogs.db --counts --columns
[{"table": "Gosh", "count": 0, "columns": ["c1", "c2", "c3"]},
{"table": "Gosh2", "count": 0, "columns": ["c1", "c2", "c3"]},
{"table": "dogs", "count": 2, "columns": ["id", "age", "name"]}]
The `` --nl `` , `` --csv `` and `` --no-headers `` options are all available.
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.. _cli_inserting_data:
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Inserting data
==============
If you have data as JSON, you can use `` sqlite-utils insert tablename `` to insert it into a database. The table will be created with the correct (automatically detected) columns if it does not already exist.
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You can pass in a single JSON object or a list of JSON objects, either as a filename or piped directly to standard-in (by using `` - `` as the filename).
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Here's the simplest possible example::
$ echo '{"name": "Cleo", "age": 4}' | sqlite-utils insert dogs.db dogs -
To specify a column as the primary key, use `` --pk=column_name `` .
If you feed it a JSON list it will insert multiple records. For example, if `` dogs.json `` looks like this::
[
{
"id": 1,
"name": "Cleo",
"age": 4
},
{
"id": 2,
"name": "Pancakes",
"age": 2
},
{
"id": 3,
"name": "Toby",
"age": 6
}
]
You can import all three records into an automatically created `` dogs `` table and set the `` id `` column as the primary key like so::
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$ sqlite-utils insert dogs.db dogs dogs.json --pk=id
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You can also import newline-delimited JSON using the `` --nl `` option. Since `Datasette <https://datasette.readthedocs.io/> `__ can export newline-delimited JSON, you can combine the two tools like so::
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$ curl -L "https://latest.datasette.io/fixtures/facetable.json?_shape=array&_nl=on" \
| sqlite-utils insert nl-demo.db facetable - --pk=id --nl
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This also means you pipe `` sqlite-utils `` together to easily create a new SQLite database file containing the results of a SQL query against another database::
$ sqlite-utils json sf-trees.db \
"select TreeID, qAddress, Latitude, Longitude from Street_Tree_List" --nl \
| sqlite-utils insert saved.db trees - --nl
# This creates saved.db with a single table called trees:
$ sqlite-utils csv saved.db "select * from trees limit 5"
TreeID,qAddress,Latitude,Longitude
141565,501X Baker St,37.7759676911831,-122.441396661871
232565,940 Elizabeth St,37.7517102172731,-122.441498017841
119263,495X Lakeshore Dr,,
207368,920 Kirkham St,37.760210314285,-122.47073935813
188702,1501 Evans Ave,37.7422086702947,-122.387293152263
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Upserting data
==============
Upserting works exactly like inserting, with the exception that if your data has a primary key that matches an already exsting record that record will be replaced with the new data.
After running the above `` dogs.json `` example, try running this::
$ echo '{"id": 2, "name": "Pancakes", "age": 3}' | \
sqlite-utils upsert dogs.db dogs - --pk=id
This will replace the record for id=2 (Pancakes) with a new record with an updated age.
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.. _cli_fts:
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Configuring full-text search
============================
You can enable SQLite full-text search on a table and a set of columns like this::
$ sqlite-utils enable-fts mydb.db documents title summary
This will use SQLite's FTS5 module by default. Use `` --fts4 `` if you want to use FTS4::
$ sqlite-utils enable-fts mydb.db documents title summary --fts4
The `` enable-fts `` command will populate the new index with all existing documents. If you later add more documents you will need to use `` populate-fts `` to cause them to be indexed as well::
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$ sqlite-utils populate-fts mydb.db documents title summary
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Vacuum
======
You can run VACUUM to optimize your database like so::
$ sqlite-utils vacuum mydb.db
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Optimize
========
The optimize command can dramatically reduce the size of your database if you are using SQLite full-text search. It runs OPTIMIZE against all of our FTS4 and FTS5 tables, then runs VACUUM.
If you just want to run OPTIMIZE without the VACUUM, use the `` --no-vacuum `` flag.
::
# Optimize all FTS tables and then VACUUM
$ sqlite-utils optimize mydb.db
# Optimize but skip the VACUUM
$ sqlite-utils optimize --no-vacuum mydb.db