I am writing this blog to add columns in our database table which would compatible with old version of database. Here I use Alter Table command on my onUpgrade() method where I make condition for the ...

The ALTER TABLE.. ADD COLUMN statement adds a column to an existing table. This operation is online in TiDB, which means that neither reads or writes to the table are blocked by adding a column.

A-schema-changes C-bug Code not up to spec/doc, specs & docs deemed correct. Solution expected to change code/behavior. T-sql-foundations SQL Foundations Team (formerly SQL Schema + SQL Sessions) ...

The DICTIONARY tables component is specified in the FROM clause of a SELECT statement. DICTIONARY is a reserved libref for use only in PROC SQL. Data from DICTIONARY tables are generated at run time.