JDBC- SQL时空查询

Question

trajectory table

       OBJID      PLACE       
                 7               H  
                 8               Q  
                 9               W  
                10               A  
                 7               H  
                 8               A  
                 1                S  
                 2           D  
                 4           G  
                 7           B  
                 3           K  
                 7           H  
                 3           I  
                 7           C  

i have trajectory table as shown in above. I want a spatio-temporal query using JDBC-SQL to retrieve results.

1. " Find all OBJIDs that move from place H to place B"
2. "Find all usertrajectories that move from place H to place B"

here for example in this image objid 7 moves from H to B, hence the result should be .

output

query1
objids : 7


query2

7 trajectory is HHBHC

I want a SQL query for this.

Answer 1

Query your table WHERE objid = ? then take the results and concatenate them together as you pull from the ResultSet .