Extract single repeating XML node through whole XML result - oracle

Question

Given the following XML sample below, how can I extract all <table_no> values from top to bottom using Oracle XML extraction.
Based on below, I would expect to see the following individual rows from my select:
1
4
2
11
Table: tickets
Column holding XML: ticket_col
XML code:
<xml>
<ticket_order>
<table_no>1<table_no/>
<waiter>Jack<waiter/>
<total_people>12<total_people/>
</ticket_order>
<ticket_order>
<table_no>4<table_no/>
<waiter>Jackie<waiter/>
<total_people>3<total_people/>
</ticket_order>
<ticket_order>
<table_no>2<table_no/>
<waiter>Sally<waiter/>
<total_people>2<total_people/>
</ticket_order>
<ticket_order>
<table_no>11<table_no/>
<waiter>Mike<waiter/>
<total_people>6<total_people/>
</ticket_order>
</xml>

Answer 1

You can use XMLTable(); with (fixed) sample XML as a string in-line:
select x.*
from xmltable(
'/xml/ticket_order'
passing xmltype('<xml>
<ticket_order>
<table_no>1</table_no>
<waiter>Jack</waiter>
<total_people>12</total_people>
</ticket_order>
<ticket_order>
<table_no>4</table_no>
<waiter>Jackie</waiter>
<total_people>3</total_people>
</ticket_order>
<ticket_order>
<table_no>2</table_no>
<waiter>Sally</waiter>
<total_people>2</total_people>
</ticket_order>
<ticket_order>
<table_no>11</table_no>
<waiter>Mike</waiter>
<total_people>6</total_people>
</ticket_order>
</xml>')
columns table_no number path 'table_no'
) x;
TABLE_NO
----------
1
4
2
11
If the XML is a string (VARCHAR2 or CLOB) in a table you would pass it in via a cross join:
select x.*
from your_table t
cross join xmltable(
'/xml/ticket_order'
passing xmltype(t.xml_string)
columns table_no number path 'table_no'
) x;
If it's already am XMLType in the table you woudl skip that conversion:
select x.*
from your_table t
cross join xmltable(
'/xml/ticket_order'
passing t.xml
columns table_no number path 'table_no'
) x;
You can get multiple columns at once; and the generated relatinal column name doesn't have to be the same as the node name:
select x.*
from your_table t
cross join xmltable(
'/xml/ticket_order'
passing t.xml
columns table_number number path 'table_no',
server varchar2(10) path 'waiter',
covers number path 'total_people'
) x;
TABLE_NUMBER SERVER COVERS
------------ ---------- ----------
1 Jack 12
4 Jackie 3
2 Sally 2
11 Mike 6
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