Need to extract the below query data along with header in csv file using shell script.

Below is the query.

```
SELECT SourceIdentifier,SourceFileName,ProfitCentre2,PlantCode,
tax_retur ReturnPeriod,document_number DocumentNumber,TO_CHAR(invoice_generation_date,'YYYY-MM-DD')
Docume,Original,customer_name CustomerName,NVL(sns_pos,new_state_code)POS,PortCode,NEW_HSN_CODE HSNorSAC,(SGSATE+UTGSATE) Stat,(SGS+UT)StateUT,Userde FROM arbor.INV_REPO_FINA WHERE UPPER(document_type)='INV' AND UPPER(backout_flag)='VALID' AND new_gst_id_new IS NOT NULL AND new_charges<>0 AND taxable_adj=0
UNION
SELECT SourceIdentifier,SourceFileName,ProfitCentre2,PlantCode,
tax_retur ReturnPeriod,document_number DocumentNumber,TO_CHAR(invoice_generation_date,'YYYY-MM-DD')
Docume,Original,customer_name CustomerName,NVL(sns_pos,new_state_code)POS,PortCode, NEW_HSN_CODE HSNorSAC,(SGSATE+UTGSATE) Stat,(SGS+UTG)StateUT,Userde FROM arbor.INV_REPO_FINA WHERE UPPER(document_type)='INV' AND UPPER(backout_flag)='VALID' AND new_gst_id_new IS NOT NULL AND new_charges<>0 AND  taxable_adj<>0

```

Could please let me know if below approach to fetch data using shell script is correct and script is correct.

```
#!/bin/bash
file="output.csv"
sqlplus -s username/password@Oracle_SID << EOF
SPOOL $file

select 'SourceIdentifier','SourceFileName','ProfitCentre2','PlantCode',
'tax_retur ReturnPeriod','document_number DocumentNumber','TO_CHAR(invoice_generation_date,'YYYY-MM-DD') Docume','Original','customer_name CustomerName','NVL(sns_pos,new_state_code)POS','PortCode','NEW_HSN_CODE HSNorSAC','(SGSATE+UTGSATE) Stat','(SGS+UT)StateUT','Userde' from dual
Union all
select 'TO_CHAR(SourceIdentifier)','TO_CHAR(SourceFileName)','TO_CHAR(ProfitCentre2)','TO_CHAR(PlantCode)',
'TO_CHAR(tax_retur ReturnPeriod)','TO_CHAR(document_number DocumentNumber)','TO_CHAR(invoice_generation_date,'YYYY-MM-DD')
Docume','TO_CHAR(Original)','TO_CHAR(customer_name CustomerName)','TO_CHAR(NVL(sns_pos,new_state_code)POS)','TO_CHAR(PortCode)','TO_CHAR(NEW_HSN_CODE HSNorSAC)','TO_CHAR((SGSATE+UTGSATE) Stat)','TO_CHAR((SGS+UT)StateUT)','TO_CHAR(Userde)' from
(SELECT SourceIdentifier,SourceFileName,ProfitCentre2,PlantCode,
tax_retur ReturnPeriod,document_number DocumentNumber,TO_CHAR(invoice_generation_date,'YYYY-MM-DD')
Docume,Original,customer_name CustomerName,NVL(sns_pos,new_state_code)POS,PortCode,NEW_HSN_CODE HSNorSAC,(SGSATE+UTGSATE) Stat,(SGS+UT)StateUT,Userde FROM arbor.INV_REPO_FINA WHERE UPPER(document_type)='INV' AND UPPER(backout_flag)='VALID' AND new_gst_id_new IS NOT NULL AND new_charges<>0 AND taxable_adj=0
UNION
SELECT SourceIdentifier,SourceFileName,ProfitCentre2,PlantCode,
tax_retur ReturnPeriod,document_number DocumentNumber,TO_CHAR(invoice_generation_date,'YYYY-MM-DD')
Docume,Original,customer_name CustomerName,NVL(sns_pos,new_state_code)POS,PortCode, NEW_HSN_CODE HSNorSAC,(SGSATE+UTGSATE) Stat,(SGS+UTG)StateUT,Userde FROM arbor.INV_REPO_FINA WHERE UPPER(document_type)='INV' AND UPPER(backout_flag)='VALID' AND new_gst_id_new IS NOT NULL AND new_charges<>0 AND  taxable_adj<>0)

SPOOL OFF
EXIT
EOF

```