Android開發相關:(06)快速瞭解SQLite

[sql] // Set the column headers to show in the tool 
sqlite>. headers on 
 
// select all rows from a table 
select * from table1; 
 
// count the number of rows in a table 
select count(*) from table1; 
 
// select a specific set of columns 
select col1, col2 from table1; 
 
// select distinct values in a column 
select distinct col1 from table1; 
 
// counting the distinct valus 
select count(col1) from (select distinct col1 from table1); 
 
// group by 
select count(*), col1 from table1 group by col1; 
 
// regular inner join 
select * from table1 t1, table2 t2 where t1.col1 = t2.col1; 
 
// left outer join 
// give me everything in t1 even though there are no rows in t2 
select * from table t1 left outer join table2 t2 on t1.col1 = t2.col1 where …. 
 // Set the column headers to show in the tool
 sqlite>. headers on
 
 // select all rows from a table
 select * from table1;
 
 // count the number of rows in a table
 select count(*) from table1;
 
 // select a specific set of columns
 select col1, col2 from table1;
 
 // select distinct values in a column
 select distinct col1 from table1;
 
 // counting the distinct valus
 select count(col1) from (select distinct col1 from table1);
 
 // group by
 select count(*), col1 from table1 group by col1;
 
 // regular inner join
 select * from table1 t1, table2 t2 where t1.col1 = t2.col1;
 
 // left outer join
 // give me everything in t1 even though there are no rows in t2
 select * from table t1 left outer join table2 t2 on t1.col1 = t2.col1 where ….

摘自 horsttnann的專欄

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