![]() ![]() If your tables are significant in size, this will save you a lot of time. To get a drop column statement for each table.īut, you might consider creating views of your tables that don't contain the seq columns, and then exporting to PostgreSQL using those views. You can also do CONCAT('ALTER TABLE ',TABLE_NAME, ' DROP COLUMN seq ') AS stmt Click on the Drop button underneath the list of columns. These statements will zero out your seq columns. Place a checkmark next to the column(s) you wish to drop (delete permanently). ALTER TABLE mytable DROP COLUMN mycolumn but I can't seem to find any info on how to remove all of the column fields, but keep the column itself (which will be populated with NULL fields. Then you could run these statements one by one. How do I delete all of the fields in a column, but WITHOUT deleting the column itself There is plenty of info on how to delete a MYSQL table column e.g. This will produce a result set like this: UPDATE table_a SET seq = 0 To drop a column from a table, use the syntax: alter table drop column .SELECT DISTINCTĬONCAT('UPDATE ',TABLE_NAME, ' SET seq = 0 ') AS stmt You could then adapt that query to, for example, create a list of statements like this. First, write ALTER TABLE, followed by the name of the table you want to change (in our example, product ). Hence, the MySQL ALTER COLUMN performs the query to add, modify, delete, or rename any columns in a table in the database server. This query will return that list of tables for the database you're currently using. SQL Drop Column Syntax MySQL ALTER TABLE Customer DROP BirthDate SQL Server ALTER TABLE Customer DROP COLUMN BirthDate Oracle ALTER TABLE Customer. This deletecolumn variable is set equal to a mysqlquery() function that has the parameter ALTER. You might start by using the information_schema in MySQL to discover which of your tables have a seq column in them. After we do this, we create a variable named deletecolumn. ![]() A fat-finger error could really mess you up.) ![]() (Most database folks don't routinely drop columns from a database in production it takes a lot of time during which the tables are inaccessible, and it's destructive. You need to generate a list of SQL statements and then run them, somehow. There isn't a simple magical expression to just do this. ![]()
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