Help Center/ GaussDB(DWS)/ Tool Guide/ DSC/ Teradata Syntax Migration/ Data Manipulation Language (DML)/ DELETE
Updated on 2024-07-19 GMT+08:00
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DELETE

DELETE (short key abbreviated as DEL) is an ANSI-compliant SQL syntax operator used to delete existing records from a table. DSC supports the Teradata DELETE statement and its short key DEL. The DELETE statement that does not contain the WHERE clause is migrated to TRUNCATE in GaussDB(DWS). Use the deleteToTruncate parameter to enable or disable this behavior.

Input: DELETE

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DEL FROM tab1
 WHERE a =10;

Output

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DELETE FROM tab1
 WHERE a =10;

Input: DELETE without WHERE - Migrated to TRUNCATE if deletetoTruncate=TRUE

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DELETE FROM ${schemaname} . "tablename" ALL;

Output

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TRUNCATE
     TABLE
          ${schemaname} . "tablename";

In DELETE, the same table is used in DELETE and FROM clauses with / without WHERE clause

Input

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DELETE DP_TMP.M_P_TX_SCV_REMAINING_PARTY 
FROM DP_TMP.M_P_TX_SCV_REMAINING_PARTY ALL ;
---
DELETE DP_VMCTLFW.CTLFW_Process_Id 
FROM DP_VMCTLFW.CTLFW_Process_Id 
WHERE (Process_Name =  :_spVV2 ) 
AND  (Process_Id  NOT IN (SELECT MAX(Process_Id )(NAMED Process_Id ) 
                                      FROM DP_VMCTLFW.CTLFW_Process_Id 
                                     WHERE Process_Name =  :_spVV2 )
      );
---
DELETE CPID 
FROM DP_VMCTLFW.CTLFW_Process_Id AS CPID
WHERE (Process_Name =  :_spVV2 ) 
AND  (Process_Id  NOT IN (SELECT MAX(Process_Id )(NAMED Process_Id ) 
                                      FROM DP_VMCTLFW.CTLFW_Process_Id 
                                     WHERE Process_Name =  :_spVV2 )
      );

Output

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DELETE FROM DP_TMP.M_P_TX_SCV_REMAINING_PARTY;
---
DELETE FROM DP_VMCTLFW.CTLFW_Process_Id 
WHERE (Process_Name =  :_spVV2 ) 
AND  (Process_Id  NOT IN (SELECT MAX(Process_Id )(NAMED Process_Id ) 
                                      FROM DP_VMCTLFW.CTLFW_Process_Id 
                                     WHERE Process_Name =  :_spVV2 )
      );
---
DELETE FROM DP_VMCTLFW.CTLFW_Process_Id AS CPID
WHERE (Process_Name =  :_spVV2 ) 
AND  (Process_Id  NOT IN (SELECT MAX(Process_Id )(NAMED Process_Id ) 
                                      FROM DP_VMCTLFW.CTLFW_Process_Id 
                                     WHERE Process_Name =  :_spVV2 )
      );

DELETE table_alias FROM table

Input

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SQL_Detail10124.sql
delete a
  from ${BRTL_DCOR}.BRTL_CS_POT_CUST_UMPAY_INF_S as a
 where a.DW_Snsh_Dt = cast('${v_Trx_Dt}' as date format 'yyyy-mm-dd') 
 and a.DW_Job_Seq = 1 ;
was migrated as below:
      DELETE FROM
           BRTL_DCOR.BRTL_CS_POT_CUST_UMPAY_INF_S AS a
                USING
      WHERE a.DW_Snsh_Dt = CAST( lv_mig_v_Trx_Dt AS DATE )
           AND a.DW_Job_Seq = 1 ;
SQL_Detail10449.sql
delete a
  from ${BRTL_DCOR}.BRTL_EM_YISHITONG_USR_INF as a
 where a.DW_Job_Seq = 1 ;
was migrated as below:
      DELETE FROM
           BRTL_DCOR.BRTL_EM_YISHITONG_USR_INF AS a
                USING
      WHERE a.DW_Job_Seq = 1 ;
SQL_Detail5742.sql
delete a
  from ${BRTL_DCOR}.BRTL_PD_FP_NAV_ADT_INF as a;
was migrated as 
      DELETE a
 FROM
      BRTL_DCOR.BRTL_PD_FP_NAV_ADT_INF AS a ;

Output

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SQL_Detail10124.sql
delete from ${BRTL_DCOR}.BRTL_CS_POT_CUST_UMPAY_INF_S as a
 where a.DW_Snsh_Dt = cast('${v_Trx_Dt}' as date format 'yyyy-mm-dd') 
 and a.DW_Job_Seq = 1 ;
SQL_Detail10449.sql
delete from ${BRTL_DCOR}.BRTL_EM_YISHITONG_USR_INF as a
 where a.DW_Job_Seq = 1 ;
SQL_Detail5742.sql
delete from ${BRTL_DCOR}.BRTL_PD_FP_NAV_ADT_INF as a;