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In the "lang.html" documentation file, put the CREATE TRIGGER and DROP TRIGGER

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sections in alphabetical order. (CVS 564)

FossilOrigin-Name: d1d8642b57bd0765ade730248012d58b0859c12c
This commit is contained in:
drh
2002-05-15 11:43:16 +00:00
parent b38f58b51a
commit 5b87fa2a57
3 changed files with 130 additions and 132 deletions
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14
manifest
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@ -1,5 +1,5 @@
C Add\sthe\sMakefile.in\sthat\swas\sforgotten\swith\scheckin\s#562\s(CVS\s563) C In\sthe\s"lang.html"\sdocumentation\sfile,\sput\sthe\sCREATE\sTRIGGER\sand\sDROP\sTRIGGER\nsections\sin\salphabetical\sorder.\s(CVS\s564)
D 2002-05-15T08:43:10 D 2002-05-15T11:43:16
F Makefile.in 6291a33b87d2a395aafd7646ee1ed562c6f2c28c F Makefile.in 6291a33b87d2a395aafd7646ee1ed562c6f2c28c
F Makefile.template 89e373b2dad0321df00400fa968dc14b61a03296 F Makefile.template 89e373b2dad0321df00400fa968dc14b61a03296
F README a4c0ba11354ef6ba0776b400d057c59da47a4cc0 F README a4c0ba11354ef6ba0776b400d057c59da47a4cc0
@ -127,14 +127,14 @@ F www/dynload.tcl 02eb8273aa78cfa9070dd4501dca937fb22b466c
F www/faq.tcl 45bdb18b75ac3aa1befec42985fb892413aac0bb F www/faq.tcl 45bdb18b75ac3aa1befec42985fb892413aac0bb
F www/formatchng.tcl 2ce21ff30663fad6618198fe747ce675df577590 F www/formatchng.tcl 2ce21ff30663fad6618198fe747ce675df577590
F www/index.tcl d0c52fbf031d0a3ee6d9d77aa669d5a4b24b6130 F www/index.tcl d0c52fbf031d0a3ee6d9d77aa669d5a4b24b6130
F www/lang.tcl a22cf9eff51e65ec5aa39b1efb5b7952d800ac06 F www/lang.tcl be7a241fe3dbb145ff25fe951c3d8ad16b543a1f
F www/mingw.tcl f1c7c0a7f53387dd9bb4f8c7e8571b7561510ebc F www/mingw.tcl f1c7c0a7f53387dd9bb4f8c7e8571b7561510ebc
F www/opcode.tcl bdec8ef9f100dbd87bbef8976c54b88e43fd8ccc F www/opcode.tcl bdec8ef9f100dbd87bbef8976c54b88e43fd8ccc
F www/speed.tcl da8afcc1d3ccc5696cfb388a68982bc3d9f7f00f F www/speed.tcl da8afcc1d3ccc5696cfb388a68982bc3d9f7f00f
F www/sqlite.tcl 8b5884354cb615049aed83039f8dfe1552a44279 F www/sqlite.tcl 8b5884354cb615049aed83039f8dfe1552a44279
F www/tclsqlite.tcl 1db15abeb446aad0caf0b95b8b9579720e4ea331 F www/tclsqlite.tcl 1db15abeb446aad0caf0b95b8b9579720e4ea331
F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218 F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218
P 794bf67b6b36fce8854d5daff12f21dbb943240c P 29b8330ca6bfe32c499a045189683100f2b15246
R 08d6d280437ddbf6c3512d0683d6a10e R a27803f7b286e7959f11eb8469f192e0
U danielk1977 U drh
Z 654e041ad87e42741720cd7b74aa49a7 Z a84814eb63e1343d44fc3775f1b09115

2
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@ -1 +1 @@
29b8330ca6bfe32c499a045189683100f2b15246 d1d8642b57bd0765ade730248012d58b0859c12c

246
www/lang.tcl
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@ -1,7 +1,7 @@
# #
# Run this Tcl script to generate the sqlite.html file. # Run this Tcl script to generate the sqlite.html file.
# #
set rcsid {$Id: lang.tcl,v 1.34 2002/05/15 08:30:15 danielk1977 Exp $} set rcsid {$Id: lang.tcl,v 1.35 2002/05/15 11:43:16 drh Exp $}
puts {<html> puts {<html>
<head> <head>
@ -345,6 +345,118 @@ CREATE TABLE statement is synthesized and store in <b>sqlite_master</b>
in place of the original command. in place of the original command.
</p> </p>
} }
Section {CREATE TRIGGER} createtrigger
Syntax {sql-statement} {
CREATE TRIGGER <trigger-name> [ BEFORE | AFTER ]
<database-event> ON <table-name>
<trigger-action>
}
Syntax {database-event} {
DELETE |
INSERT |
UPDATE |
UPDATE OF <column-list>
}
Syntax {trigger-action} {
[ FOR EACH ROW ] [ WHEN <expression> ]
BEGIN
<trigger-step> ; [ <trigger-step> ; ]*
END
}
Syntax {trigger-step} {
<update-statement> | <insert-statement> |
<delete-statement> | <select-statement>
}
puts {
<p>The CREATE TRIGGER statement is used to add triggers to the
database schema. Triggers are database operations (the <i>trigger-action</i>)
that are automatically performed when a specified database event (the
<i>database-event</i>) occurs. </p>
<p>A trigger may be specified to fire whenever a DELETE, INSERT or UPDATE of a
particular database table occurs, or whenever an UPDATE of one or more
specified columns of a table are updated.</p>
<p>At this time SQLite supports only FOR EACH ROW triggers, not FOR EACH
STATEMENT triggers. Hence explicitly specifying FOR EACH ROW is optional. FOR
EACH ROW implies that the SQL statements specified as <i>trigger-steps</i>
may be executed (depending on the WHEN clause) for each database row being
inserted, updated or deleted by the statement causing the trigger to fire.</p>
<p>Both the WHEN clause and the <i>trigger-steps</i> may access elements of
the row being inserted, deleted or updated using references of the form
"NEW.<i>column-name</i>" and "OLD.<i>column-name</i>", where
<i>column-name</i> is the name of a column from the table that the trigger
is associated with. OLD and NEW references may only be used in triggers on
<i>trigger-event</i>s for which they are relevant, as follows:</p>
<table border=0 cellpadding=10>
<tr>
<td valign="top" align="right" width=120><i>INSERT</i></td>
<td valign="top">NEW references are valid</td>
</tr>
<tr>
<td valign="top" align="right" width=120><i>UPDATE</i></td>
<td valign="top">NEW and OLD references are valid</td>
</tr>
<tr>
<td valign="top" align="right" width=120><i>DELETE</i></td>
<td valign="top">OLD references are valid</td>
</tr>
</table>
</p>
<p>If a WHEN clause is supplied, the SQL statements specified as <i>trigger-steps</i> are only executed for rows for which the WHEN clause is true. If no WHEN clause is supplied, the SQL statements are executed for all rows.</p>
<p>The specified <i>trigger-time</i> determines when the <i>trigger-steps</i>
will be executed relative to the insertion, modification or removal of the
associated row.</p>
<p>An ON CONFLICT clause may be specified as part of an UPDATE or INSERT
<i>trigger-step</i>. However if an ON CONFLICT clause is specified as part of
the statement causing the trigger to fire, then this conflict handling
policy is used instead.</p>
<p>Triggers are automatically dropped when the table that they are
associated with is dropped.</p>
<p>Triggers may be created on views, as well as ordinary tables. If one or
more INSERT, DELETE or UPDATE triggers are defined on a view, then it is not
an error to execute an INSERT, DELETE or UPDATE statement on the view,
respectively. Thereafter, executing an INSERT, DELETE or UPDATE on the view
causes the associated triggers to fire. The real tables underlying the view
are not modified (except possibly explicitly, by a trigger program).</p>
<p><b>Example:</b></p>
<p>Assuming that customer records are stored in the "customers" table, and
that order records are stored in the "orders" table, the following trigger
ensures that all associated orders are redirected when a customer changes
his or her address:</p>
}
Example {
CREATE TRIGGER update_customer_address UPDATE OF address ON customers
BEGIN
UPDATE orders SET address = new.address WHERE customer_name = old.name;
END;
}
puts {
<p>With this trigger installed, executing the statement:</p>
}
Example {
UPDATE customers SET address = '1 Main St.' WHERE name = 'Jack Jones';
}
puts {
<p>causes the following to be automatically executed:</p>
}
Example {
UPDATE orders SET address = '1 Main St.' WHERE customer_name = 'Jack Jones';
}
Section {CREATE VIEW} {createview} Section {CREATE VIEW} {createview}
@ -398,6 +510,15 @@ Syntax {sql-command} {
DROP TABLE <table-name> DROP TABLE <table-name>
} }
Section {DROP TRIGGER} droptrigger
Syntax {sql-statement} {
DROP TRIGGER <trigger-name>
}
puts {
<p>Used to drop a trigger from the database schema. Note that triggers
are automatically dropped when the associated table is dropped.</p>
}
puts { puts {
<p>The DROP TABLE statement consists of the keywords "DROP TABLE" followed <p>The DROP TABLE statement consists of the keywords "DROP TABLE" followed
by the name of the table. The table named is completely removed from by the name of the table. The table named is completely removed from
@ -1091,129 +1212,6 @@ the database backend and VACUUM has become a no-op.
</p> </p>
} }
Section {CREATE TRIGGER} createtrigger
Syntax {sql-statement} {
CREATE TRIGGER <trigger-name> [ BEFORE | AFTER ]
<database-event>
<trigger-action>
}
Syntax {database-event} {
DELETE |
INSERT |
UPDATE |
UPDATE OF <column-list>
ON <table-name>
}
Syntax {trigger-action} {
[ FOR EACH ROW ] [ WHEN <expression> ]
BEGIN
<trigger-step> ; [ <trigger-step> ; ]*
END
}
Syntax {trigger-step} {
<update-statement> | <insert-statement> |
<delete-statement> | <select-statement>
}
puts {
<p>The CREATE TRIGGER statement is used to add triggers to the
database schema. Triggers are database operations (the <i>trigger-action</i>)
that are automatically performed when a specified database event (the
<i>database-event</i>) occurs. </p>
<p>A trigger may be specified to fire whenever a DELETE, INSERT or UPDATE of a
particular database table occurs, or whenever an UPDATE of one or more
specified columns of a table are updated.</p>
<p>At this time SQLite supports only FOR EACH ROW triggers, not FOR EACH
STATEMENT triggers. Hence explicitly specifying FOR EACH ROW is optional. FOR
EACH ROW implies that the SQL statements specified as <i>trigger-steps</i>
may be executed (depending on the WHEN clause) for each database row being
inserted, updated or deleted by the statement causing the trigger to fire.</p>
<p>Both the WHEN clause and the <i>trigger-steps</i> may access elements of
the row being inserted, deleted or updated using references of the form
"NEW.<i>column-name</i>" and "OLD.<i>column-name</i>", where
<i>column-name</i> is the name of a column from the table that the trigger
is associated with. OLD and NEW references may only be used in triggers on
<i>trigger-event</i>s for which they are relevant, as follows:</p>
<table border=0 cellpadding=10>
<tr>
<td valign="top" align="right" width=120><i>INSERT</i></td>
<td valign="top">NEW references are valid</td>
</tr>
<tr>
<td valign="top" align="right" width=120><i>UPDATE</i></td>
<td valign="top">NEW and OLD references are valid</td>
</tr>
<tr>
<td valign="top" align="right" width=120><i>DELETE</i></td>
<td valign="top">OLD references are valid</td>
</tr>
</table>
</p>
<p>If a WHEN clause is supplied, the SQL statements specified as <i>trigger-steps</i> are only executed for rows for which the WHEN clause is true. If no WHEN clause is supplied, the SQL statements are executed for all rows.</p>
<p>The specified <i>trigger-time</i> determines when the <i>trigger-steps</i>
will be executed relative to the insertion, modification or removal of the
associated row.</p>
<p>An ON CONFLICT clause may be specified as part of an UPDATE or INSERT
<i>trigger-step</i>. However if an ON CONFLICT clause is specified as part of
the statement causing the trigger to fire, then this conflict handling
policy is used instead.</p>
<p>Triggers are automatically dropped when the table that they are
associated with is dropped.</p>
<p>Triggers may be created on views, as well as ordinary tables. If one or
more INSERT, DELETE or UPDATE triggers are defined on a view, then it is not
an error to execute an INSERT, DELETE or UPDATE statement on the view,
respectively. Thereafter, executing an INSERT, DELETE or UPDATE on the view
causes the associated triggers to fire. The real tables underlying the view
are not modified (except possibly explicitly, by a trigger program).</p>
<p><b>Example:</b></p>
<p>Assuming that customer records are stored in the "customers" table, and
that order records are stored in the "orders" table, the following trigger
ensures that all associated orders are redirected when a customer changes
his or her address:</p>
}
Example {
CREATE TRIGGER update_customer_address UPDATE OF address ON customers
BEGIN
UPDATE orders SET address = new.address WHERE customer_name = old.name;
END;
}
puts {
<p>With this trigger installed, executing the statement:</p>
}
Example {
UPDATE customers SET address = '1 Main St.' WHERE name = 'Jack Jones';
}
puts {
<p>causes the following to be automatically executed:</p>
}
Example {
UPDATE orders SET address = '1 Main St.' WHERE customer_name = 'Jack Jones';
}
Section {DROP TRIGGER} droptrigger
Syntax {sql-statement} {
DROP TRIGGER <trigger-name>
}
puts {
<p>Used to drop a trigger from the database schema. Note that triggers
are automatically dropped when the associated table is dropped.</p>
}
puts { puts {
<p><hr /></p> <p><hr /></p>