Documentation Source Text

  {{ATTACH DATABASE} attach}
  {{DETACH DATABASE} detach}
  {REINDEX reindex}
  {{ALTER TABLE} altertable}
  {{ANALYZE} analyze}
}] {
  foreach {s_title s_tag} $section {}
  if {$s_tag=="pragma.html"} {
    set url $s_tag
  } else {
    set url lang_$s_tag.html
  }
  puts "<li><a href=\"$url\">$s_title</a></li>"
  incr i
  if {$i==15} {
    puts "</ul></td><td valign=\"top\"><ul>"
  }
}
</tcl>
</ul></td></tr></table>

in that one database are analyzed.  If the argument is a table name,
then only indices associated with that one table are analyzed.</p>

<p>The initial implementation stores all statistics in a single
table named <b>sqlite_stat1</b>.  Future enhancements may create
additional tables with the same name pattern except with the "1"
changed to a different digit.  The <b>sqlite_stat1</b> table cannot
be <a href="lang_droptable.html">DROP</a>ped,
but all the content can be <a href="lang_delete.html">DELETE</a>d which has the
same effect.</p>

<tcl>
Section {ATTACH DATABASE} attach

Syntax {sql-statement} {
ATTACH [DATABASE] <database-filename> AS <database-name>
}
</tcl>

<p>The ATTACH DATABASE statement adds another database 
file to the current database connection.  If the filename contains 
punctuation characters it must be quoted.  The names 'main' and 
'temp' refer to the main database and the database used for 
temporary tables.  These cannot be detached.  Attached databases 
are removed using the <a href="lang_detach.html">DETACH DATABASE</a> 
statement.</p>

<p>You can read from and write to an attached database and you
can modify the schema of the attached database.  This is a new
feature of SQLite version 3.0.  In SQLite 2.8, schema changes
to attached databases were not allowed.</p>

<p>
Transactions can be started manually using the BEGIN
command.  Such transactions usually persist until the next
COMMIT or ROLLBACK command.  But a transaction will also 
ROLLBACK if the database is closed or if an error occurs
and the ROLLBACK conflict resolution algorithm is specified.
See the documentation on the <a href="lang_conflict.html">ON CONFLICT</a>
clause for additional information about the ROLLBACK
conflict resolution algorithm.
</p>

<p>
END TRANSACTION is an alias for COMMIT.
</p>

all CREATE INDEX statements
are read from the <b>sqlite_master</b> table and used to regenerate
SQLite's internal representation of the index layout.</p>

<p>If the optional IF NOT EXISTS clause is present and another index
with the same name aleady exists, then this command becomes a no-op.</p>

<p>Indexes are removed with the <a href="lang_dropindex.html">DROP INDEX</a> 
command.</p>


<tcl>
##############################################################################
Section {CREATE TABLE} {createtable}

constraint conflict resolution algorithm for that constraint.
The default is abort ABORT.  Different constraints within the same
table may have different default conflict resolution algorithms.
If an COPY, INSERT, or UPDATE command specifies a different conflict
resolution algorithm, then that algorithm is used in place of the
default algorithm specified in the CREATE TABLE statement.
See the section titled
<a href="lang_conflict.html">ON CONFLICT</a> for additional information.</p>

<p>CHECK constraints are supported as of version 3.3.0.  Prior
to version 3.3.0, CHECK constraints were parsed but not enforced.</p>

<p>There are no arbitrary limits on the number
of columns or on the number of constraints in a table.
The total amount of data in a single row is limited to about

The text of CREATE TEMPORARY TABLE statements are stored in the
<b>sqlite_temp_master</b> table.
</p>

<p>If the optional IF NOT EXISTS clause is present and another table
with the same name aleady exists, then this command becomes a no-op.</p>

<p>Tables are removed using the <a href="lang_droptable.html">DROP TABLE</a> 
statement.  </p>

<tcl>
##############################################################################
Section {CREATE TRIGGER} createtrigger

Syntax {sql-statement} {

the statement that caused the trigger program to execute and any subsequent
    trigger programs that would of been executed are abandoned. No database
    changes are rolled back.  If the statement that caused the trigger program
    to execute is itself part of a trigger program, then that trigger program
    resumes execution at the beginning of the next step.
</p>

<p>Triggers are removed using the 
<a href="lang_droptrigger.html">DROP TRIGGER</a> statement.</p>


<tcl>
###############################################################################
Section {CREATE VIEW} {createview}

Syntax {sql-command} {
CREATE [TEMP | TEMPORARY] VIEW [IF NOT EXISTS] [<database-name>.] <view-name> AS <select-statement>
}
</tcl>

<p>The CREATE VIEW command assigns a name to a pre-packaged 
<a href="lang_select.html">SELECT</a>
statement.  Once the view is created, it can be used in the FROM clause
of another SELECT in place of a table name.
</p>

<p>If the "TEMP" or "TEMPORARY" keyword occurs in between "CREATE"
and "VIEW" then the view that is created is only visible to the
process that opened the database and is automatically deleted when
the database is closed.</p>

<p> If a &lt;database-name&gt; is specified, then the view is created in 
the named database. It is an error to specify both a &lt;database-name&gt;
and the TEMP keyword, unless the &lt;database-name&gt; is "temp". If no
database name is specified, and the TEMP keyword is not present,
the table is created in the main database.</p>

<p>You cannot COPY, DELETE, INSERT or UPDATE a view.  Views are read-only 
in SQLite.  However, in many cases you can use a 
<a href="lang_createtrigger.html">TRIGGER</a> on the view to accomplish 
the same thing.  Views are removed 
with the <a href="lang_dropview.html">DROP VIEW</a> 
command.</p>

<tcl>
##############################################################################
Section {CREATE VIRTUAL TABLE} {createvtab}

Syntax {sql-command} {

the SQLite database connection using
sqlite3_create_module()
prior to issuing the CREATE VIRTUAL TABLE statement.
The module takes zero or more comma-separated arguments.
The arguments can be just about any text as long as it has balanced
parentheses.  The argument syntax is sufficiently general that the
arguments can be made to appear as column definitions in a traditional
<a href="lang_createtable.html">CREATE TABLE</a> statement.  
SQLite passes the module arguments directly
to the module without any interpretation.  It is the responsibility
of the module implementation to parse and interpret its own arguments.</p>

<p>A virtual table is destroyed using the ordinary
<a href="lang_droptable.html">DROP TABLE</a> statement.  There is no
DROP VIRTUAL TABLE statement.</p>

<tcl>
##############################################################################
Section DELETE delete

Syntax {sql-statement} {

Syntax {sql-command} {
DETACH [DATABASE] <database-name>
}
</tcl>

<p>This statement detaches an additional database connection previously 
attached using the <a href="lang_attach.html">ATTACH DATABASE</a> statement.  
It is possible to have the same database file attached multiple times using 
different names, and detaching one connection to a file will leave the 
others intact.</p>

<p>This statement will fail if SQLite is in the middle of a transaction.</p>


<tcl>
##############################################################################
Section {DROP INDEX} dropindex

Syntax {sql-command} {
DROP INDEX [IF EXISTS] [<database-name> .] <index-name>
}
</tcl>

<p>The DROP INDEX statement removes an index added
with the <a href="lang_createindex.html">
CREATE INDEX</a> statement.  The index named is completely removed from
the disk.  The only way to recover the index is to reenter the
appropriate CREATE INDEX command.</p>

<p>The DROP INDEX statement does not reduce the size of the database 
file in the default mode.
Empty space in the database is retained for later INSERTs.  To 
remove free space in the database, 
use the <a href="lang_vacuum.html">VACUUM</a> 
command.  If AUTOVACUUM mode is enabled for a database then space
will be freed automatically by DROP INDEX.</p>


<tcl>
##############################################################################
Section {DROP TABLE} droptable

Syntax {sql-command} {
DROP TABLE [IF EXISTS] [<database-name>.] <table-name>
}
</tcl>

<p>The DROP TABLE statement removes a table added with the <a href=
"lang_createtable.html">CREATE TABLE</a> statement.  The name specified is the
table name.  It is completely removed from the database schema and the 
disk file.  The table can not be recovered.  All indices associated 
with the table are also deleted.</p>

<p>The DROP TABLE statement does not reduce the size of the database 
file in the default mode.  Empty space in the database is retained for
later INSERTs.  To 
remove free space in the database, 
use the <a href="lang_vacuum.html">VACUUM</a> 
command.  If AUTOVACUUM mode is enabled for a database then space
will be freed automatically by DROP TABLE.</p>

<p>The optional IF EXISTS clause suppresses the error that would normally
result if the table does not exist.</p>

<tcl>
##############################################################################
Section {DROP TRIGGER} droptrigger
Syntax {sql-statement} {
DROP TRIGGER [IF EXISTS] [<database-name> .] <trigger-name>
}
</tcl>

<p>The DROP TRIGGER statement removes a trigger created by the 
<a href="lang_createtrigger.html">CREATE TRIGGER</a> statement.  The trigger is 
deleted from the database schema. Note that triggers are automatically 
dropped when the associated table is dropped.</p>

<tcl>
##############################################################################
Section {DROP VIEW} dropview

Syntax {sql-command} {
DROP VIEW [IF EXISTS] <view-name>
}
</tcl>

<p>The DROP VIEW statement removes a view created by the <a href=
"lang_createview.html">CREATE VIEW</a> statement.  The name specified is the 
view name.  It is removed from the database schema, but no actual data 
in the underlying base tables is modified.</p>

<tcl>
##############################################################################
Section EXPLAIN explain

name in the column list.  A new entry is made in the table
for every row of the SELECT result.  The SELECT may be simple
or compound.</p>

<p>The optional conflict-clause allows the specification of an alternative
constraint conflict resolution algorithm to use during this one command.
See the section titled
<a href="lang_conflict.html">ON CONFLICT</a> for additional information.
For compatibility with MySQL, the parser allows the use of the
single keyword <a href="lange_replace.html">REPLACE</a> as an 
alias for "INSERT OR REPLACE".
</p>

<tcl>
##############################################################################
Section {ON CONFLICT clause} conflict

Syntax {conflict-clause} {

Syntax {sql-statement} {
REPLACE INTO [<database-name> .] <table-name> [( <column-list> )] VALUES ( <value-list> ) |
REPLACE INTO [<database-name> .] <table-name> [( <column-list> )] <select-statement>
}
</tcl>

<p>The REPLACE command is an alias for the "INSERT OR REPLACE" variant
of the <a href="lang_insert.html">INSERT</a> command.  
This alias is provided for
compatibility with MySQL.  See the 
<a href="lang_insert.html">INSERT</a> command documentation for additional
information.</p>  

<tcl>
###############################################################################
Section SELECT select

Syntax {sql-statement} {

to the right.  The expressions may use the values of other columns.
All expressions are evaluated before any assignments are made.
A WHERE clause can be used to restrict which rows are updated.</p>

<p>The optional conflict-clause allows the specification of an alternative
constraint conflict resolution algorithm to use during this one command.
See the section titled
<a href="lang_conflict.html">ON CONFLICT</a> for additional information.</p>


<tcl>
##############################################################################
Section VACUUM vacuum

Syntax {sql-statement} {