Release 0.21.0

[ea-rus]

Changes:

• Optimized join tables from different databases Optimize join tables from different databases #412
• Cte support Cte support #413
• Support combining queries: intersect, except Support combining queries: intersect, except #411
• Support insert from union Fix insert from union #408
• Support CAST(a AS decimal(x, y)) Support CAST(a AS decimal(x, y)) #410

Fixes:

• Fix modulo precedence Fix modulo precedence #409
• fix standard render 'interval': number have to be quoted Parser fixes #2 #414
• fix case with default value for sqlachemy render Parser fixes #2 #414
• ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED in window function Parser fixes #1 #415
• simple form of case Parser fixes #1 #415
• query with cte to one integration Parser fixes #1 #415