UPDATE keyword

Updates data in a database table.

Syntax

note

• the same columnName cannot be specified multiple times after the SET keyword as it would be ambiguous
• the designated timestamp column cannot be updated as it would lead to altering history of the time-series data
• If the target partition is attached by a symbolic link, the partition is read-only. UPDATE operation on a read-only partition will fail and generate an error.

Examples

Update with constant

UPDATE trades SET price = 125.34 WHERE symbol = 'AAPL';

Update with function

UPDATE book SET mid = (bid + ask)/2 WHERE symbol = 'AAPL';

Update with subquery

UPDATE spreads s SET s.spread = p.ask - p.bid FROM prices p WHERE s.symbol = p.symbol;

Update with multiple joins

WITH up AS (
    SELECT p.ask - p.bid AS spread, s.timestamp
    FROM prices p
    JOIN instruments i ON p.symbol = i.symbol
    WHERE i.type = 'BOND'
)
UPDATE spreads s
SET s.spread = up.spread
FROM up
WHERE s.timestamp = up.timestamp;

Update with a sub-query

WITH up AS (
    SELECT symbol, spread, ts
    FROM temp_spreads
    WHERE timestamp between '2022-01-02' and '2022-01-03'
)
UPDATE spreads s
SET spread = up.spread
FROM up
WHERE up.ts = s.ts AND s.symbol = up.symbol;