SQLite - Commands


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This chapter will take you through simple and useful commands used by SQLite programmers. These commands are called SQLite dot commands and exception with these commands is that they should not be terminated by a semi-colon (;).

Let's start with typing a simple sqlite3 command at command prompt which will provide you with SQLite command prompt where you will issue various SQLite commands.

$sqlite3
SQLite version 3.3.6
Enter ".help" for instructions
sqlite>

For a listing of the available dot commands, you can enter ".help" any time. For example −

sqlite>.help

The above command will display a list of various important SQLite dot commands, which are listed in the following table.

Sr.No. Command & Description
1

.backup ?DB? FILE

Backup DB (default "main") to FILE

2

.bail ON|OFF

Stop after hitting an error. Default OFF

3

.databases

List names and files of attached databases

4

.dump ?TABLE?

Dump the database in an SQL text format. If TABLE specified, only dump tables matching LIKE pattern TABLE

5

.echo ON|OFF

Turn command echo on or off

6

.exit

Exit SQLite prompt

7

.explain ON|OFF

Turn output mode suitable for EXPLAIN on or off. With no args, it turns EXPLAIN on

8

.header(s) ON|OFF

Turn display of headers on or off

9

.help

Show this message

10

.import FILE TABLE

Import data from FILE into TABLE

11

.indices ?TABLE?

Show names of all indices. If TABLE specified, only show indices for tables matching LIKE pattern TABLE

12

.load FILE ?ENTRY?

Load an extension library

13

.log FILE|off

Turn logging on or off. FILE can be stderr/stdout

14

.mode MODE

Set output mode where MODE is one of −

  • csv − Comma-separated values

  • column − Left-aligned columns.

  • html − HTML <table> code

  • insert − SQL insert statements for TABLE

  • line − One value per line

  • list − Values delimited by .separator string

  • tabs − Tab-separated values

  • tcl − TCL list elements

15

.nullvalue STRING

Print STRING in place of NULL values

16

.output FILENAME

Send output to FILENAME

17

.output stdout

Send output to the screen

18

.print STRING...

Print literal STRING

19

.prompt MAIN CONTINUE

Replace the standard prompts

20

.quit

Exit SQLite prompt

21

.read FILENAME

Execute SQL in FILENAME

22

.schema ?TABLE?

Show the CREATE statements. If TABLE specified, only show tables matching LIKE pattern TABLE

23

.separator STRING

Change separator used by output mode and .import

24

.show

Show the current values for various settings

25

.stats ON|OFF

Turn stats on or off

26

.tables ?PATTERN?

List names of tables matching a LIKE pattern

27

.timeout MS

Try opening locked tables for MS milliseconds

28

.width NUM NUM

Set column widths for "column" mode

29

.timer ON|OFF

Turn the CPU timer measurement on or off

Let's try .show command to see default setting for your SQLite command prompt.

sqlite>.show
     echo: off
  explain: off
  headers: off
     mode: column
nullvalue: ""
   output: stdout
separator: "|"
    width:
sqlite>

Make sure there is no space in between sqlite> prompt and dot command, otherwise it will not work.

Formatting Output

You can use the following sequence of dot commands to format your output.

sqlite>.header on
sqlite>.mode column
sqlite>.timer on
sqlite>

The above setting will produce the output in the following format.

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          California  20000.0
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0
7           James       24          Houston     10000.0
CPU Time: user 0.000000 sys 0.000000

The sqlite_master Table

The master table holds the key information about your database tables and it is called sqlite_master. You can see its schema as follows −

sqlite>.schema sqlite_master

This will produce the following result.

CREATE TABLE sqlite_master (
   type text,
   name text,
   tbl_name text,
   rootpage integer,
   sql text
);


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