SQLite Commands

Things to consider when dealing with SQLite: 

• Data type integrity is not maintained in SQLite, you can put a value of a certain data type in a column of another datatype (put string in an integer and vice versa).

• Referential integrity is not maintained in SQLite, there is no FOREIGN KEY constraints or JOIN statements.

• SQLite Full Unicode support is optional and not installed by default.

sqlite3 command at command prompt which will provide you 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" at any time. 

sqlite>.help

 

Command	Description
.backup ?DB? FILE	Backup DB (default "main") to FILE
.bail ON|OFF	Stop after hitting an error. Default OFF
.databases	List names and files of attached databases
.dump ?TABLE?	Dump the database in an SQL text format. If TABLE specified, only dump tables matching LIKE pattern TABLE.
.echo ON|OFF	Turn command echo on or off
.exit	Exit SQLite prompt
.explain ON|OFF	Turn output mode suitable for EXPLAIN on or off. With no args, it turns EXPLAIN on.
.header(s) ON|OFF	Turn display of headers on or off
.help	Show this message
.import FILE TABLE	Import data from FILE into TABLE
.indices ?TABLE?	Show names of all indices. If TABLE specified, only show indices for tables matching LIKE pattern TABLE.
.load FILE ?ENTRY?	Load an extension library
.log FILE|off	Turn logging on or off. FILE can be stderr/stdout
.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
.nullvalue STRING	Print STRING in place of NULL values
.output FILENAME	Send output to FILENAME
.output stdout	Send output to the screen
.print STRING...	Print literal STRING
.prompt MAIN CONTINUE	Replace the standard prompts
.quit	Exit SQLite prompt
.read FILENAME	Execute SQL in FILENAME
.schema ?TABLE?	Show the CREATE statements. If TABLE specified, only show tables matching LIKE pattern TABLE.
.separator STRING	Change separator used by output mode and .import
.show	Show the current values for various settings
.stats ON|OFF	Turn stats on or off
.tables ?PATTERN?	List names of tables matching a LIKE pattern
.timeout MS	Try opening locked tables for MS milliseconds
.width NUM NUM	Set column widths for "column" mode
.timer ON|OFF	Turn the CPU timer measurement on or off

 .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>

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

);

Select command: 

Sqlite> select * from mytable;

EMP_ID  NAME    AGE     ADDRESS  SALARY

----------  ----------  ----------  ----------      ----------

1             John            32          SF              20000.0

2             Smith          25          NJ              15000.0

3             Elie             23          SD              20000.0