This section is a translation specification for the compound statements
This section is a work in progress, information may change in the future.
Some parts in the output code are omitted for clarity reasons.
General description
The basic unit of a PL/SQL source program is the block, which groups related declarations and statements.
A PL/SQL block is defined by the keywords DECLARE, BEGIN, EXCEPTION, and END. These keywords divide the block into a declarative part, an executable part, and an exception-handling part. Only the executable part is required. (PL/SQL Anonymous Blocks)
The BEGIN...END block in Oracle can have the following characteristics:
Be nested.
Contain the DECLARE statement for variables.
Group multiple SQL or PL/SQL statements.
Oracle syntax
[DECLARE <Variable declaration>]
BEGIN
<Executable statements>
[EXCEPTION <Exception handler>]
END
DECLARE
age NUMBER := 18;
BEGIN
IF age >= 18 THEN
DBMS_OUTPUT.PUT_LINE('You are an adult.');
ELSE
DBMS_OUTPUT.PUT_LINE('You are a minor.');
END IF;
END;
Statement processed.
You are an adult.
Snowflake
When calling a procedure or user-defined function (UDF), generating code is needed to support the equivalence as call_results variable. In this case, is used to print the information.
BEGIN
DECLARE
day_of_week NUMBER := 3;
BEGIN
CASE day_of_week
WHEN 1 THEN DBMS_OUTPUT.PUT_LINE('Sunday');
WHEN 2 THEN DBMS_OUTPUT.PUT_LINE('Monday');
WHEN 3 THEN DBMS_OUTPUT.PUT_LINE('Tuesday');
WHEN 4 THEN DBMS_OUTPUT.PUT_LINE('Wednesday');
WHEN 5 THEN DBMS_OUTPUT.PUT_LINE('Thursday');
WHEN 6 THEN DBMS_OUTPUT.PUT_LINE('Friday');
WHEN 7 THEN DBMS_OUTPUT.PUT_LINE('Saturday');
ELSE DBMS_OUTPUT.PUT_LINE('Invalid day');
END CASE;
END;
END;
Statement processed.
Tuesday
Snowflake
When calling a procedure or user-defined function (UDF), generating code is needed to support the equivalence as call_results variable. In this case, is used to print the information.
Anonymous block in Oracle may have calls to procedures. Furthermore, the following documentation may be useful: SnowConvert Procedure documentation.
The following example uses the OUT parameters, the information about the current transformation can be found here: SnowConvert OUTPUT Parameters
Oracle
IN -> Oracle_04.sql
-- Procedure declaration
CREATE OR REPLACE PROCEDURE calculate_sum(
p_num1 IN NUMBER,
p_num2 IN NUMBER,
p_result OUT NUMBER
)
IS
BEGIN
-- Calculate the sum of the two numbers
p_result := p_num1 + p_num2;
END;
/
-- Anonymous block with a procedure call
DECLARE
-- Declare variables to hold the input and output values
v_num1 NUMBER := 10;
v_num2 NUMBER := 20;
v_result NUMBER;
BEGIN
-- Call the procedure with the input values and get the result
calculate_sum(v_num1, v_num2, v_result);
-- Display the result
DBMS_OUTPUT.PUT_LINE('The sum of ' || v_num1 || ' and ' || v_num2 || ' is ' || v_result);
END;
/
Statement processed.
The sum of 10 and 20 is 30
Snowflake
OUT -> Oracle_04.sql
-- Procedure declaration
CREATE OR REPLACE PROCEDURE calculate_sum (p_num1 NUMBER(38, 18), p_num2 NUMBER(38, 18), p_result NUMBER(38, 18)
)
RETURNS VARIANT
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$
BEGIN
-- Calculate the sum of the two numbers
p_result := :p_num1 + :p_num2;
RETURN p_result;
END;
$$;
-- Anonymous block with a procedure call
DECLARE
-- Declare variables to hold the input and output values
v_num1 NUMBER(38, 18) := 10;
v_num2 NUMBER(38, 18) := 20;
v_result NUMBER(38, 18);
call_results VARIANT;
BEGIN
call_results := (
CALL
-- Call the procedure with the input values and get the result
calculate_sum(:v_num1, :v_num2, :v_result)
);
v_result := :call_results;
-- Display the result
--** SSC-FDM-OR0035 - CHECK UDF IMPLEMENTATION FOR DBMS_OUTPUT.PUT_LINE_UDF. **
call_results := (
CALL DBMS_OUTPUT.PUT_LINE_UDF('The sum of ' || NVL(:v_num1 :: STRING, '') || ' and ' || NVL(:v_num2 :: STRING, '') || ' is ' || NVL(:v_result :: STRING, ''))
);
RETURN call_results;
END;
Notice that in Oracle, the block BEGIN...END should use the EXECUTE IMMEDIATE statement to run alter session statements.
Oracle
IN -> Oracle_05.sql
DECLARE
lv_sql_txt VARCHAR2(200);
BEGIN
lv_sql_txt := 'ALTER SESSION SET nls_date_format = ''DD-MM-YYYY''';
EXECUTE IMMEDIATE lv_sql_txt;
END;
Statement processed.
Done
Snowflake
The following warning may be added in the future:
/*** MSC-WARNING - MSCEWI3058 - NLS_DATE_FORMAT SESSION PARAMETER DOES NOT ENFORCE THE INPUT FORMAT IN ORACLE ***/
OUT -> Oracle_05.sql
DECLARE
lv_sql_txt VARCHAR(200);
BEGIN
lv_sql_txt := 'ALTER SESSION SET nls_date_format = ''DD-MM-YYYY''';
!!!RESOLVE EWI!!! /*** SSC-EWI-0030 - THE STATEMENT BELOW HAS USAGES OF DYNAMIC SQL. ***/!!!!!!RESOLVE EWI!!! /*** SSC-EWI-0027 - THE FOLLOWING STATEMENT USES A VARIABLE/LITERAL WITH AN INVALID QUERY AND IT WILL NOT BE EXECUTED ***/!!!
EXECUTE IMMEDIATE :lv_sql_txt;
END;
anonymous block
Done
6. Cursors
The following example displays the usage of a cursor inside a BEGIN...END block. Review the following documentation to learn more: Cursor documentation.
Oracle
IN -> Oracle_06.sql
CREATE TABLE employee (
ID_Number NUMBER,
emp_Name VARCHAR(200),
emp_Phone NUMBER
);
INSERT INTO employee VALUES (1, 'NameA NameZ', 1234567890);
INSERT INTO employee VALUES (2, 'NameB NameY', 1234567890);
DECLARE
var1 VARCHAR(20);
CURSOR cursor1 IS SELECT emp_Name FROM employee ORDER BY ID_Number;
BEGIN
OPEN cursor1;
FETCH cursor1 INTO var1;
CLOSE cursor1;
DBMS_OUTPUT.PUT_LINE(var1);
END;
Statement processed.
NameA NameZ
Snowflake
When calling a procedure or user-defined function (UDF), generating code is needed to support the equivalence as call_results variable. In this case, is used to print the information.
CREATE OR REPLACE TABLE employee (
ID_Number NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/,
emp_Name VARCHAR(200),
emp_Phone NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;
INSERT INTO employee
VALUES (1, 'NameA NameZ', 1234567890);
INSERT INTO employee
VALUES (2, 'NameB NameY', 1234567890);
DECLARE
var1 VARCHAR(20);
cursor1 CURSOR
FOR
SELECT emp_Name FROM
employee
ORDER BY ID_Number;
call_results VARIANT;
BEGIN
OPEN cursor1;
FETCH cursor1 INTO
:var1;
CLOSE cursor1;
--** SSC-FDM-OR0035 - CHECK UDF IMPLEMENTATION FOR DBMS_OUTPUT.PUT_LINE_UDF. **
call_results := (
CALL DBMS_OUTPUT.PUT_LINE_UDF(:var1)
);
RETURN call_results;
END;
CREATE TABLE employee (
ID_Number NUMBER,
emp_Name VARCHAR(200),
emp_Phone NUMBER
);
INSERT INTO employee VALUES (1, 'NameA NameZ', 1234567890);
INSERT INTO employee VALUES (2, 'NameB NameY', 1234567890);
DECLARE
var_Result NUMBER;
BEGIN
SELECT COUNT(*) INTO var_Result FROM employee;
DBMS_OUTPUT.PUT_LINE(var_Result);
END;
Statement processed.
2
Snowflake
When calling a procedure or user-defined function (UDF), generating code is needed to support the equivalence as call_results variable. In this case, is used to print the information.
CREATE OR REPLACE TABLE employee (
ID_Number NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/,
emp_Name VARCHAR(200),
emp_Phone NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;
INSERT INTO employee
VALUES (1, 'NameA NameZ', 1234567890);
INSERT INTO employee
VALUES (2, 'NameB NameY', 1234567890);
DECLARE
var_Result NUMBER(38, 18);
call_results VARIANT;
BEGIN
SELECT COUNT(*) INTO
:var_Result
FROM
employee;
--** SSC-FDM-OR0035 - CHECK UDF IMPLEMENTATION FOR DBMS_OUTPUT.PUT_LINE_UDF. **
call_results := (
CALL DBMS_OUTPUT.PUT_LINE_UDF(:var_Result)
);
RETURN call_results;
END;
anonymous block
2
8. Join Statements
For more information review the following documentation: Joins documentation.
Oracle
IN -> Oracle_08.sql
CREATE TABLE t1 (col1 INTEGER);
CREATE TABLE t2 (col1 INTEGER);
INSERT INTO t1 (col1) VALUES (2);
INSERT INTO t1 (col1) VALUES (3);
INSERT INTO t1 (col1) VALUES (4);
INSERT INTO t2 (col1) VALUES (1);
INSERT INTO t2 (col1) VALUES (2);
INSERT INTO t2 (col1) VALUES (2);
INSERT INTO t2 (col1) VALUES (3);
DECLARE
total_price FLOAT;
CURSOR cursor1 IS SELECT t1.col1 as FirstTable, t2.col1 as SecondTable
FROM t1 INNER JOIN t2
ON t2.col1 = t1.col1
ORDER BY 1,2;
BEGIN
total_price := 0.0;
FOR rec IN cursor1 LOOP
total_price := total_price + rec.FirstTable;
END LOOP;
DBMS_OUTPUT.PUT_LINE(total_price);
END;
Statement processed.
7
Snowflake
When calling a procedure or user-defined function (UDF), generating code is needed to support the equivalence as call_results variable. In this case, is used to print the information.
CREATE OR REPLACE TABLE t1 (col1 INTEGER)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;
CREATE OR REPLACE TABLE t2 (col1 INTEGER)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;
INSERT INTO t1(col1) VALUES (2);
INSERT INTO t1(col1) VALUES (3);
INSERT INTO t1(col1) VALUES (4);
INSERT INTO t2(col1) VALUES (1);
INSERT INTO t2(col1) VALUES (2);
INSERT INTO t2(col1) VALUES (2);
INSERT INTO t2(col1) VALUES (3);
DECLARE
total_price FLOAT;
cursor1 CURSOR
FOR
SELECT t1.col1 as FIRSTTABLE, t2.col1 as SECONDTABLE
FROM
t1
INNER JOIN
t2
ON t2.col1 = t1.col1
ORDER BY 1,2;
call_results VARIANT;
BEGIN
total_price := 0.0;
OPEN cursor1;
--** SSC-PRF-0004 - THIS STATEMENT HAS USAGES OF CURSOR FOR LOOP **
FOR rec IN cursor1 DO
total_price :=
!!!RESOLVE EWI!!! /*** SSC-EWI-OR0036 - TYPES RESOLUTION ISSUES, ARITHMETIC OPERATION '+' MAY NOT BEHAVE CORRECTLY BETWEEN AproxNumeric AND unknown ***/!!!
:total_price + rec.FIRSTTABLE;
END FOR;
CLOSE cursor1;
--** SSC-FDM-OR0035 - CHECK UDF IMPLEMENTATION FOR DBMS_OUTPUT.PUT_LINE_UDF. **
call_results := (
CALL DBMS_OUTPUT.PUT_LINE_UDF(:total_price)
);
RETURN call_results;
END;
9. Exception handling
Oracle
IN -> Oracle_09.sql
DECLARE
v_result NUMBER;
BEGIN
v_result := 1 / 0;
EXCEPTION
WHEN ZERO_DIVIDE THEN
DBMS_OUTPUT.PUT_LINE( SQLERRM );
END;
Statement processed.
ORA-01476: divisor is equal to zero
Snowflake
ZERO_DIVIDE exception in Snowflake is not supported.
OUT -> Oracle_09.sql
DECLARE
v_result NUMBER(38, 18);
error_results VARIANT;
BEGIN
v_result := 1 / 0;
EXCEPTION
WHEN ZERO_DIVIDE THEN
--** SSC-FDM-OR0035 - CHECK UDF IMPLEMENTATION FOR DBMS_OUTPUT.PUT_LINE_UDF. **
error_results := (
CALL DBMS_OUTPUT.PUT_LINE_UDF( SQLERRM )
);
RETURN error_results;
END;
anonymous block
Division by zero
Known issues
Exceptions that use GOTO statements may be affected too.
Cursor functionality may be adapted under current restrictions on translations.
Related EWIs
SSC-EWI-0027:The following statement uses a variable/literal with an invalid query and it will not be executed.
SSC-EWI-OR0036: Types resolution issues, the arithmetic operation may not behave correctly between string and date.
