sqlite3 is a terminal-based front-end to the SQLite library that can evaluate queries interactively and display the results in multiple formats. sqlite3 can also be used within shell scripts and other applications to provide batch processing features.
For example, to create a new database file named "mydata.db", create a table named "memos" and insert a couple of records into that table:
$
sqlite3 mydata.db
SQLite version 3.1.3
Enter ".help" for instructions
sqlite>
create table memos(text, priority INTEGER);
sqlite>
insert into memos values(deliver project description, 10);
sqlite>
insert into memos values(lunch with Christine, 100);
sqlite>
select * from memos;
deliver project description|10
lunch with Christine|100
sqlite>
If no database name is supplied, the ATTACH sql command can be used to attach to existing or create new database files. ATTACH can also be used to attach to multiple databases within the same interactive session. This is useful for migrating data between databases, possibly changing the schema along the way.
Optionally, a SQL statement or set of SQL statements can be supplied as a single argument. Multiple statements should be separated by semi-colons.
For example:
$
sqlite3 -line mydata.db select * from memos where priority > 20;
text = lunch with Christine
priority = 100
The interactive interpreter offers a set of meta-commands that can be used to control the output format, examine the currently attached database files, or perform administrative operations upon the attached databases (such as rebuilding indices). Meta-commands are always prefixed with a dot (.).
A list of available meta-commands can be viewed at any time by issuing the .help command. For example:
sqlite> .help
csv Comma-separated values column Left-aligned columns. (See .width) 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 sqlite> |cc . |
Tag | Description |
---|---|
-init file | Read and execute commands from file , which can contain a mix of SQL statements and meta-commands. |
-echo | Print commands before execution. |
-[no]header | |
Turn headers on or off. | |
-column | Query results will be displayed in a table like form, using whitespace characters to separate the columns and align the output. |
-html | Query results will be output as simple HTML tables. |
-line | Query results will be displayed with one value per line, rows separated by a blank line. Designed to be easily parsed by scripts or other programs |
-list | Query results will be displayed with the separator (|, by default) character between each field value. The default. |
-separator separator | |
Set output field separator. Default is |. | |
-nullvalue string | |
Set string used to represent NULL values. Default is (empty string). | |
-version | Show SQLite version. |
-help |
Show help on options and exit.
|
o The default configuration is established as follows:
mode = LIST separator = "|" main prompt = "sqlite> " continue prompt = " ...> " |cc . |
o If the file ~/.sqliterc exists, it is processed first. can be found in the users home directory, it is read and processed. It should generally only contain meta-commands.
o If the -init option is present, the specified file is processed.
o All other command line options are processed.
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