[IMPALA-7832] Support IF NOT EXISTS in alter table add columns

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: Impala 3.1.0
• Fix Version/s: Impala 3.2.0
• Component/s: Frontend
• Labels: ramp-up
• Epic Color: ghx-label-6
• Assignee: Fredy Wijaya
• Reporter: Thomas Tauber-Marshall
• Created: 07/Nov/18 22:49
• Updated: 09/Mar/23 17:28
• Resolved: 24/Jan/19 17:02

Description

alter table <table_name> add [if not exists] columns (<name> <type> [, <name> <type>...])

would add the column only if a column of the same name does not already exist

Probably worth checking out what other databases do in different situations, eg. if the column already exists but with a different type, if "replace" is used instead of "add", etc.

Issue Links

• relates to: IMPALA-11463 Support IF NOT EXISTS in alter table add columns for kudu table

Sub-Tasks

• Impala Doc: Doc IF NOT EXISTS in ALTER TABLE: Closed