Oracle 23c

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create table OIT (INFTXT) as
select to_clob(q'^<?xml version="1.0"?>
<tdfmt sel-start="218">31 05 2022 Rico Strydom<br/>
Op verzoek (zie e-mail) garanties overplaatsen....<br/>
    <br/>
OVERBOEKING CREDITGELDEN:<br/>BANKCODE: 1171<br/>T.L.V.: VERP. NL99BANK999999999999<br/>T.G.V.: RC NL00BANK000000000000<br/>
BEDRAG: EUR 9999999<br/>BESCHRIJVING: Vrijgave verpanding creditgelden AA98987987987 ivm overzetten zekerheid naar BGF<br/>
    <br/>
</tdfmt>^')
from dual
union all
select to_clob(q'^<?xml version="1.0"?>
<tdfmt sel-start="219"></tdfmt>^')
from dual
2 rows affected

SELECT XMLSERIALIZE(DOCUMENT XMLQUERY(q'^
                                copy $i := $doc modify (
                                    for $j in $i/tdfmt/text()[1]
                                return 
                                    insert node ( $text, $br, '&#xa;' ) before $j
                                )
                                return $i
                               ^'
        PASSING
            XMLTYPE(OIT.INFTXT)  AS "doc",
            LENGTH(EXTRACTVALUE(XMLTYPE(OIT.INFTXT),'tdfmt/text()[1]')) AS "len",
            'NEW TEXT TO INSERT' AS "text",
            XMLTYPE('<br/>')            AS "br"
        RETURNING CONTENT)  AS CLOB INDENT SIZE=4 )
        AS NEW_INFTXT_A
FROM OIT


NEW_INFTXT_A


<?xml version="1.0"?>
<tdfmt sel-start="218">NEW TEXT TO INSERT<br/>
31 05 2022 Rico Strydom<br/>
Op verzoek (zie e-mail) garanties overplaatsen....<br/>
    <br/>
OVERBOEKING CREDITGELDEN:<br/>BANKCODE: 1171<br/>T.L.V.: VERP. NL99BANK999999999999<br/>T.G.V.: RC NL00BANK000000000000<br/>
BEDRAG: EUR 9999999<br/>BESCHRIJVING: Vrijgave verpanding creditgelden AA98987987987 ivm overzetten zekerheid naar BGF<br/>
    <br/>
</tdfmt>


<?xml version="1.0"?>
<tdfmt sel-start="219"/>



SELECT XMLSERIALIZE(DOCUMENT XMLQUERY(q'^
                                copy $i := $doc modify (
                                    for $j in $i/*
                                return 
                                    insert node ( $text, $br, '&#xa;' ) into $j
                                )
                                return $i
                               ^'
        PASSING
            XMLTYPE(OIT.INFTXT)  AS "doc",
            LENGTH(EXTRACTVALUE(XMLTYPE(OIT.INFTXT),'tdfmt/text()[1]')) AS "len",
            'NEW TEXT TO INSERT' AS "text",
            XMLTYPE('<br/>')            AS "br"
        RETURNING CONTENT)  AS CLOB INDENT SIZE=4 )
        AS NEW_INFTXT_B
FROM OIT


NEW_INFTXT_B


<?xml version="1.0"?>
<tdfmt sel-start="218">31 05 2022 Rico Strydom<br/>
Op verzoek (zie e-mail) garanties overplaatsen....<br/>
    <br/>
OVERBOEKING CREDITGELDEN:<br/>BANKCODE: 1171<br/>T.L.V.: VERP. NL99BANK999999999999<br/>T.G.V.: RC NL00BANK000000000000<br/>
BEDRAG: EUR 9999999<br/>BESCHRIJVING: Vrijgave verpanding creditgelden AA98987987987 ivm overzetten zekerheid naar BGF<br/>
    <br/>NEW TEXT TO INSERT<br/>
</tdfmt>


<?xml version="1.0"?>
<tdfmt sel-start="219">NEW TEXT TO INSERT<br/>
</tdfmt>



SELECT XMLSERIALIZE(DOCUMENT XMLQUERY(q'^                                      
                                if ($len>0) 
                                then    
                                    copy $i := $doc modify (
                                        for $j in $i/tdfmt/text()[1]
                                    return 
                                        insert node ( $text, $br, '&#xa;' ) before $j
                                    )
                                    return $i
                                else    
                                    copy $i := $doc modify (
                                        for $j in $i/*
                                    return 
                                        insert node ( $text, $br, '&#xa;' ) into $j
                                    )
                                    return $i
                               ^'
        PASSING
            XMLTYPE(OIT.INFTXT)  AS "doc",
            LENGTH(EXTRACTVALUE(XMLTYPE(OIT.INFTXT),'tdfmt/text()[1]')) AS "len",
            'NEW TEXT TO INSERT' AS "text",
            XMLTYPE('<br/>')            AS "br"
        RETURNING CONTENT)  AS CLOB INDENT SIZE=4 )
        AS NEW_INFTXT1
FROM OIT


NEW_INFTXT1


<tdfmt sel-start="218">NEW TEXT TO INSERT<br/>
31 05 2022 Rico Strydom<br/>
Op verzoek (zie e-mail) garanties overplaatsen....<br/>
    <br/>
OVERBOEKING CREDITGELDEN:<br/>BANKCODE: 1171<br/>T.L.V.: VERP. NL99BANK999999999999<br/>T.G.V.: RC NL00BANK000000000000<br/>
BEDRAG: EUR 9999999<br/>BESCHRIJVING: Vrijgave verpanding creditgelden AA98987987987 ivm overzetten zekerheid naar BGF<br/>
    <br/>
</tdfmt>


<tdfmt sel-start="219">NEW TEXT TO INSERT<br/>
</tdfmt>



SELECT XMLSERIALIZE(DOCUMENT XMLQUERY(q'^                                      
                                copy $i := $doc modify (
                                    if ($len>0) 
                                    then    
                                        for $j in $i/tdfmt/text()[1]
                                        return 
                                        insert node ( $text, $br, '&#xa;' ) before $j
                                    else    
                                        for $j in $i/*
                                        return 
                                        insert node ( $text, $br, '&#xa;' ) into $j
                                )
                                return $i
                               ^'
        PASSING
            XMLTYPE(OIT.INFTXT)  AS "doc",
            LENGTH(EXTRACTVALUE(XMLTYPE(OIT.INFTXT),'tdfmt/text()[1]')) AS "len",
            'NEW TEXT TO INSERT' AS "text",
            XMLTYPE('<br/>')            AS "br"
        RETURNING CONTENT)  AS CLOB INDENT SIZE=4 )
        AS NEW_INFTXT1
FROM OIT


NEW_INFTXT1


<?xml version="1.0"?>
<tdfmt sel-start="218">NEW TEXT TO INSERT<br/>
31 05 2022 Rico Strydom<br/>
Op verzoek (zie e-mail) garanties overplaatsen....<br/>
    <br/>
OVERBOEKING CREDITGELDEN:<br/>BANKCODE: 1171<br/>T.L.V.: VERP. NL99BANK999999999999<br/>T.G.V.: RC NL00BANK000000000000<br/>
BEDRAG: EUR 9999999<br/>BESCHRIJVING: Vrijgave verpanding creditgelden AA98987987987 ivm overzetten zekerheid naar BGF<br/>
    <br/>
</tdfmt>


<?xml version="1.0"?>
<tdfmt sel-start="219">NEW TEXT TO INSERT<br/>
</tdfmt>



SELECT XMLSERIALIZE(DOCUMENT XMLQUERY(q'^                                      
                                copy $i := $doc modify (
                                    for $j in $i/tdfmt/text()[1]
                                        return 
                                            if ($len>0) 
                                            then    
                                                insert node ( $text, $br, '&#xa;' ) before $j
                                            else    
                                                insert node ( $text, $br, '&#xa;' ) into $j
                                )
                                return $i
                               ^'
        PASSING
            XMLTYPE(OIT.INFTXT)  AS "doc",
            LENGTH(EXTRACTVALUE(XMLTYPE(OIT.INFTXT),'tdfmt/text()[1]')) AS "len",
            'NEW TEXT TO INSERT' AS "text",
            XMLTYPE('<br/>')            AS "br"
        RETURNING CONTENT)  AS CLOB INDENT SIZE=4 )
        AS NEW_INFTXT1
FROM OIT


NEW_INFTXT1


<?xml version="1.0"?>
<tdfmt sel-start="218">NEW TEXT TO INSERT<br/>
31 05 2022 Rico Strydom<br/>
Op verzoek (zie e-mail) garanties overplaatsen....<br/>
    <br/>
OVERBOEKING CREDITGELDEN:<br/>BANKCODE: 1171<br/>T.L.V.: VERP. NL99BANK999999999999<br/>T.G.V.: RC NL00BANK000000000000<br/>
BEDRAG: EUR 9999999<br/>BESCHRIJVING: Vrijgave verpanding creditgelden AA98987987987 ivm overzetten zekerheid naar BGF<br/>
    <br/>
</tdfmt>


<?xml version="1.0"?>
<tdfmt sel-start="219"/>