What are the structures of PostgreSQL loops
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1. Basic LOOP statements
Using EXIT...WHEN to end the loop operation
DECLARE I NUMBER: =-3; BEGIN LOOP DBMS_OUTPUT.PUT_LINE ('I ='| | I); I: = I + 1; EXIT test_loop WHEN I > 3; END LOOP; DBMS_OUTPUT.PUT_LINE ('LOOP loop is over!') ; END; /
Use the if. Exit statement to end the loop
DECLARE I NUMBER: =-3; BEGIN LOOP DBMS_OUTPUT.PUT_LINE ('I ='| | I); I: = I + 1; IF I > 3 THEN EXIT TEST_LOOP; END IF; END LOOP; DBMS_OUTPUT.PUT_LINE ('LOOP cycle is over!') ; END; / II, WHILE...LOOP structure DECLARE I NUMBER: =-3; BEGIN WHILE (I < 4) LOOP DBMS_OUTPUT.PUT_LINE ('I ='| I); I: = I + 1; END LOOP; DBMS_OUTPUT.PUT_LINE ('LOOP loop is over!') END; / III, FOR...LOOP structure DECLARE BEGIN FOR I IN-3.. 3 LOOP DBMS_OUTPUT.PUT_LINE ('I ='| | I); END LOOP; DBMS_OUTPUT.PUT_LINE ('LOOP loop is over!') ; END; / Thank you for your reading, the above is the content of "what is the structure of the PostgreSQL loop?" after the study of this article, I believe you have a deeper understanding of what the structure of the PostgreSQL loop has, and the specific use needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!