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Still syntax error. <br />
IF not exists (select * from mytable.firstname) then alter table mytable add column firstname character varying ; END IF;<br />
ERROR: &nbsp;syntax error at or near &quot;if&quot;<br />

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Still syntax error.
IF not exists (select * from mytable.firstname) then alter table mytable add column firstname character varying ; END IF;
ERROR:  syntax error at or near "if"


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It didn't work for Postgres
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Are you just using that line or are there lines before that line?
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Are you just using that line or are there lines before that line?

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I am using postgres. &nbsp;I want to check to see if a column exists before adding a column. &nbsp;But when I tried &quot;if not exists (select * from mytable.firstname) begin alter table mytable add column firstname character varying end&quot;<br />
<br />
I got a syntax error:<br />
ERROR: &nbsp;syntax error at or near &quot;if&quot;
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I am using postgres.  I want to check to see if a column exists before adding a column.  But when I tried "if not exists (select * from mytable.firstname) begin alter table mytable add column firstname character varying end"

I got a syntax error:
ERROR:  syntax error at or near "if"

sql, check if column exists before adding

PostgreSQL is an object-relational database management system with an emphasis on extensibility and standards-compliance. As a database server, its primary function is to store data securely, supporting best practices, and to allow for retrieval at the request of other software applications. PostgreSQL implements the majority of the SQL2011 standard, is ACID-compliant and transactional using multiversion concurrency control (MVCC), and handles complex SQL queries using many indexing methods that are not available in other databases. It is cross-platform and runs on many operating systems including Linux, FreeBSD, OS X, Solaris, and Microsoft Windows.