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POAttempting to create variable variables in mysql ONLY. (Not using PHP)
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  1. POAttempting to create variable variables in mysql ONLY. (Not using PHP)
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    copied!<h2>Context</h2> <p>I have a dynamically generated .sql file that contains a series of insert statements which are going to be used for inserting data into many different tables that are dependent on other tables.</p> <p>After each insert statement is ran, if a particular table has an autoincremented id column, then the text "SET @autoIncrementColumnName = LAST_INSERT_ID();" is generated which stores the last insert id of that insert statement in a mysql variable. Then if there is another INSERT statement for that particular table, the process is repeated. The problem is that each statement "SET @autoIncrementColumnName = LAST_INSERT_ID();" overwrites the previous variable before it is able to use the variable later on in the .sql file.</p> <p>So then later on in the .sql script where you see two lines like these: </p> <pre><code>INSERT INTO relatedTable (col1,col2,specialColumn,col3,col4) VALUES ('','',@autoIncrementColumnName,'',''); INSERT INTO relatedTable (col1,col2,specialColumn,col3,col4) VALUES ('','',@autoIncrementColumnName,'',''); </code></pre> <p>It needs to insert the mysql value it stored earlier but all of the variables are being overwritten except for one.</p> <h2>Two Questions</h2> <ol> <li><p>Is it possible to create variable variables using only MYSQL? Like this: </p> <pre><code>SET @dynamicVarName = CONCAT('guestCreditCardId', LAST_INSERT_ID()); SET @@dynamicVarName = LAST_INSERT_ID(); </code></pre></li> <li><p>If variable variables are not possible, what solution could I use?</p></li> </ol> <h2>Thank you so much!</h2>
 

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