Databases
StackOverflow2013
Postsdbo
PODeleting temporary tables with a stored procedure
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PODeleting temporary tables with a stored procedure
    primarykey
    data
    text
    <p>I have been trying to make a stored procedure which autodeletes temporary tables.</p> <pre><code>CREATE PROCEDURE DeleteTemp() BEGIN DECLARE no_more_rows BOOLEAN; DECLARE loop_cntr INT DEFAULT 0; DECLARE num_rows INT DEFAULT 0; DECLARE tmptablename VARCHAR(100); DECLARE tmpTables CURSOR FOR SELECT TABLE_NAME FROM information_schema.TABLES WHERE TABLE_SCHEMA='myDB' AND TABLE_NAME LIKE 'tmp%'; DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_rows = TRUE; OPEN tmpTables; SELECT FOUND_ROWS() into num_rows; the_loop: LOOP FETCH tmpTables INTO tmptablename; DROP TABLE tmptablename; IF no_more_rows THEN CLOSE tmpTables; LEAVE the_loop; END IF; END LOOP the_loop; END </code></pre> <p>However, all I get is:</p> <p>Query : call DeleteTemp Error Code : 1051 Unknown table 'tmptablename'</p> <p>How can I pass the variable tmptablename properly into the "DROP TABLE" command?</p> <hr> <p>Fixed using prepared statements.</p> <pre><code>CREATE PROCEDURE DeleteTemp() BEGIN DECLARE no_more_rows BOOLEAN; DECLARE loop_cntr INT DEFAULT 0; DECLARE num_rows INT DEFAULT 0; DECLARE tmptablename VARCHAR(100); DECLARE tmpTables CURSOR FOR SELECT TABLE_NAME FROM information_schema.TABLES WHERE TABLE_SCHEMA='MY_SCHEMA' AND TABLE_NAME LIKE 'tmp%'; DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_rows = TRUE; OPEN tmpTables; SELECT FOUND_ROWS() INTO num_rows; the_loop: LOOP FETCH tmpTables INTO tmptablename; IF no_more_rows THEN CLOSE tmpTables; LEAVE the_loop; ELSE SET @a:=CONCAT('DROP TABLE ',tmptablename); PREPARE stmt1 FROM @a; EXECUTE stmt1; DEALLOCATE PREPARE stmt1; END IF; END LOOP the_loop; END </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USΗλίας
    1. USΗλίας
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. PODeleting temporary tables with a stored procedure
      1. This table or related slice is empty.
      1. VTUpMod
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload