DELETE
NAME
delete - Delete in the databases.
SYNOPSIS
delete( [db:pointer,] tables:string, wantarray:true|false, count:integer, using:string,error:variable,delete_upload:true|false,delete_foreign:true|false, join:string, having:string, selectby:string, orderby:string, groupby:string, limit:string, args:string, uid:integer, page:integer, prefix:true|false, countperpage:integer);
DESCRIPTION
This function is used to delete elements in tables.
Since the database does not support page, limit, groupby having, join. A select is perform to get the list of uid and then a delete is perform on this list. As a consequence, the field uid must be present in the table.
Also, if delete_upload or delete_foreign is set to true (default), than a select is perform and the delete is done after.
In order to delete foreign element in table the following is perform:
If we want to delete uid 5 of table sn_test1:
- Get the UID from sn_tables for sn_test1 =⇒ uid_table
- If delete_foreign is true than
- For each foreign_table and foreign field from table sn_fields where field_type = foreign and uid_sn_tables = uid_table
- For each element in foreign_table where foreign_field = 5;
- Recusively delete uid foreign_table, element
- If delete_upload is true than
- Select field_name from sn_fields where field_type = image and uid_sn_tables = uid_table
- Select * from table sn_test1 where uid = 5;
- Delete file if any
PARAMETERS
- tables
- Specify list of tables commads separated.
- delete_upload
- Delete uploaded file.
- delete_foreign
- Delete foreign elements.
- using
- Specify using keyword.
- wantarray
- By default rows are return as a context with the name of the column. If this parameter is true, it return only the value.
- count
- If parameter page is used, then the function must calculate the number of element. If you already have this number, you can use this parameter to initialize it.
-
- join
- Specify join statement for select.
- having
- Specify having statement for select.
- selectby
- Specify condition for the WHERE statement. See args \? is replase with ?.
- noargs
- By default ? in selectby are replace by values in args. If noargs is true, no replacement is done.
- args
- Specify arguments wihin selecby to quote and replace value. All ? are replace with one arguments.
- orderby
- Specify ORDER BY statement.
- groupby
- Specify GROUP BY statement.
- limit
- Specify LIMIT statement.
- uid
- Specify UID for the WHERE statement.
- page
- Specify page number based on count and countperpage.
- prefix
- Prefix name of field with table name followed by _.
- countperpage
- Number of elements in a page.
- db
- Specify alternate database pointer as return from connect function
- Starting from version 5.6.2 if db is undefined, it will fall back to the default database of the project.
RETURN
This function return an has array with thw following elements:
- sql
- Build SQL statement.
- nbcols
- Number of columns in result.
- offset
- Offset calculated when page is specify. If not, the value is -1.
- sqlerr
- Error message if any.
- count
- Calculated count (or the one specify in parameter) if page is specify. -1 otherwise.
- error
- Specify if we got an error or not
- sqlcode
- SQL error code. 0 if no error.
- nbrows
- Number of rows in result
- rows
- List if rows. The rows can be an array of hash or an array of array if wantarray is true.
EXAMPLES
Note: In the followings examples, the _ between the { should be removed to make it work.
res={_{ delete(); }}. return .*tables must be specify.*
res={_{ delete(tables:"sn_test1"); }}. ALL records will be removed from table sn_test1
res={_{ a=delete(tables:"sn_test1",uid:1); a; }}. uid 1 will be removed from table sn_test1. return {"error":false,"sqlcode":0,"nbrows":0,"rows":[],"sql":"DELETE FROM sn_test1 WHERE sed_dev_test.uid = '1'","nbcols":0,"affrow":0,"offset":-1,"sqlerr":"","count":-1}
SEE ALSO
{{ include("includes/database.sn") }}
AUTHOR
Written by Pierre Laplante, <laplante@sednove.com>
MODIFICATIONS
1.0 2014-09-09 21:24:14 laplante@sednove.com
Edit
