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sql.join(frags, delimiter)

Joins an array of SQL fragments together using a delimiter, useful for building dynamic lists of columns, conditions, or other SQL elements.

Joins SQL fragments with a delimiter. For joining SQL fragments, NOT table joins!

PostgreSQL Parameter Limit

For large bulk inserts, you may hit PostgreSQL's parameter limit (~65,535). Consider using json_populate_recordset() or json_array_elements() instead.

Syntax​

sql.join(items: ReadonlyArray<SQL>, separator?: string): SQL

Parameters​

  • items - Array of SQL fragments to join
  • separator - String delimiter to insert between fragments (defaults to empty string)

Return value​

Returns a SQL fragment containing all joined elements joined by the separator. Return empty fragment if array is empty.

Examples​

// Column lists
const columns = ["name", "email", "age"];
sql`SELECT ${sql.join(columns.map(sql.identifier), ", ")} FROM users`;
// -> SELECT "name", "email", "age" FROM users

// WHERE conditions
const conditions = [sql`age > 18`, sql`status = 'active'`];
sql`WHERE ${sql.join(conditions.map(sql.parens), " AND ")}`;
// -> WHERE (age > 18) AND (status = 'active')

// JSON objects
const fields = ["name", "email"];
sql`json_build_object(${sql.join(
  fields.map((f) => sql`${sql.literal(f)}, ${sql.identifier(f)}`),
  ", ",
)})`;