Update wiki pages.
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commit
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13 changed files with 350 additions and 51 deletions
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@ -3,7 +3,7 @@
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[](https://circleci.com/gh/go-jet/jet/tree/develop)
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Jet is Go SQL Builder for PostgreSQL(support for MySql and OracleSql will be added later).
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Jet enables writing type safe SQL queries in Go, and ability to easily convert database query result to desired arbitrary structure.
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Jet enables writing type safe SQL queries in Go, and has ability to convert database query result to desired arbitrary structure.
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## Contents
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- [Getting Started](#getting-started)
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@ -69,21 +69,21 @@ func (d *deleteStatementImpl) Sql() (query string, args []interface{}, err error
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}
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func (d *deleteStatementImpl) DebugSql() (query string, err error) {
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return DebugSql(d)
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return debugSql(d)
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}
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func (d *deleteStatementImpl) Query(db execution.DB, destination interface{}) error {
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return Query(d, db, destination)
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return query(d, db, destination)
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}
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func (d *deleteStatementImpl) QueryContext(db execution.DB, context context.Context, destination interface{}) error {
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return QueryContext(d, db, context, destination)
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return queryContext(d, db, context, destination)
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}
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func (d *deleteStatementImpl) Exec(db execution.DB) (res sql.Result, err error) {
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return Exec(d, db)
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return exec(d, db)
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}
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func (d *deleteStatementImpl) ExecContext(db execution.DB, context context.Context) (res sql.Result, err error) {
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return ExecContext(d, db, context)
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return execContext(d, db, context)
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}
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@ -56,7 +56,7 @@ func (i *insertStatementImpl) QUERY(selectStatement SelectStatement) InsertState
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}
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func (i *insertStatementImpl) DebugSql() (query string, err error) {
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return DebugSql(i)
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return debugSql(i)
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}
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func (i *insertStatementImpl) Sql() (sql string, args []interface{}, err error) {
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@ -147,17 +147,17 @@ func (i *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
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}
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func (i *insertStatementImpl) Query(db execution.DB, destination interface{}) error {
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return Query(i, db, destination)
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return query(i, db, destination)
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}
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func (i *insertStatementImpl) QueryContext(db execution.DB, context context.Context, destination interface{}) error {
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return QueryContext(i, db, context, destination)
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return queryContext(i, db, context, destination)
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}
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func (i *insertStatementImpl) Exec(db execution.DB) (res sql.Result, err error) {
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return Exec(i, db)
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return exec(i, db)
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}
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func (i *insertStatementImpl) ExecContext(db execution.DB, context context.Context) (res sql.Result, err error) {
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return ExecContext(i, db, context)
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return execContext(i, db, context)
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}
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@ -50,7 +50,7 @@ func (l *lockStatementImpl) NOWAIT() LockStatement {
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}
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func (l *lockStatementImpl) DebugSql() (query string, err error) {
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return DebugSql(l)
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return debugSql(l)
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}
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func (l *lockStatementImpl) Sql() (query string, args []interface{}, err error) {
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@ -94,17 +94,17 @@ func (l *lockStatementImpl) Sql() (query string, args []interface{}, err error)
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}
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func (l *lockStatementImpl) Query(db execution.DB, destination interface{}) error {
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return Query(l, db, destination)
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return query(l, db, destination)
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}
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func (l *lockStatementImpl) QueryContext(db execution.DB, context context.Context, destination interface{}) error {
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return QueryContext(l, db, context, destination)
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return queryContext(l, db, context, destination)
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}
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func (l *lockStatementImpl) Exec(db execution.DB) (sql.Result, error) {
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return Exec(l, db)
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return exec(l, db)
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}
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func (l *lockStatementImpl) ExecContext(db execution.DB, context context.Context) (res sql.Result, err error) {
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return ExecContext(l, db, context)
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return execContext(l, db, context)
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}
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@ -192,7 +192,7 @@ func (s *selectStatementImpl) Sql() (query string, args []interface{}, err error
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}
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func (s *selectStatementImpl) DebugSql() (query string, err error) {
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return DebugSql(s)
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return debugSql(s)
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}
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func (s *selectStatementImpl) projections() []projection {
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@ -290,17 +290,17 @@ func (s *selectLockImpl) serialize(statement statementType, out *queryData, opti
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}
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func (s *selectStatementImpl) Query(db execution.DB, destination interface{}) error {
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return Query(s, db, destination)
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return query(s, db, destination)
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}
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func (s *selectStatementImpl) QueryContext(db execution.DB, context context.Context, destination interface{}) error {
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return QueryContext(s, db, context, destination)
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return queryContext(s, db, context, destination)
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}
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func (s *selectStatementImpl) Exec(db execution.DB) (res sql.Result, err error) {
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return Exec(s, db)
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return exec(s, db)
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}
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func (s *selectStatementImpl) ExecContext(db execution.DB, context context.Context) (res sql.Result, err error) {
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return ExecContext(s, db, context)
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return execContext(s, db, context)
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}
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@ -200,21 +200,21 @@ func (s *setStatementImpl) Sql() (query string, args []interface{}, err error) {
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}
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func (s *setStatementImpl) DebugSql() (query string, err error) {
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return DebugSql(s)
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return debugSql(s)
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}
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func (s *setStatementImpl) Query(db execution.DB, destination interface{}) error {
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return Query(s, db, destination)
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return query(s, db, destination)
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}
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func (s *setStatementImpl) QueryContext(db execution.DB, context context.Context, destination interface{}) error {
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return QueryContext(s, db, context, destination)
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return queryContext(s, db, context, destination)
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}
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func (s *setStatementImpl) Exec(db execution.DB) (res sql.Result, err error) {
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return Exec(s, db)
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return exec(s, db)
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}
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func (s *setStatementImpl) ExecContext(db execution.DB, context context.Context) (res sql.Result, err error) {
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return ExecContext(s, db, context)
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return execContext(s, db, context)
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}
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23
statement.go
23
statement.go
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@ -9,19 +9,28 @@ import (
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)
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type Statement interface {
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// String returns generated SQL as string.
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// Sql returns parametrized sql query with list of arguments.
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// err is returned if statement is not composed correctly
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Sql() (query string, args []interface{}, err error)
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// DebugSql returns debug query where every parametrized placeholder is replaced with its argument.
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// Do not use it in production. Use it only for debug purposes.
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// err is returned if statement is not composed correctly
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DebugSql() (query string, err error)
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// Query executes statement over database connection db and stores row result in destination.
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// Destination can be arbitrary structure
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Query(db execution.DB, destination interface{}) error
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// QueryContext executes statement with a context over database connection db and stores row result in destination.
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// Destination can be of arbitrary structure
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QueryContext(db execution.DB, context context.Context, destination interface{}) error
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//Exec executes statement over db connection without returning any rows.
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Exec(db execution.DB) (sql.Result, error)
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//Exec executes statement with context over db connection without returning any rows.
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ExecContext(db execution.DB, context context.Context) (sql.Result, error)
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}
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func DebugSql(statement Statement) (string, error) {
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func debugSql(statement Statement) (string, error) {
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sqlQuery, args, err := statement.Sql()
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if err != nil {
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@ -38,7 +47,7 @@ func DebugSql(statement Statement) (string, error) {
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return debugSqlQuery, nil
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}
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func Query(statement Statement, db execution.DB, destination interface{}) error {
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func query(statement Statement, db execution.DB, destination interface{}) error {
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query, args, err := statement.Sql()
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if err != nil {
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@ -48,7 +57,7 @@ func Query(statement Statement, db execution.DB, destination interface{}) error
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return execution.Query(db, context.Background(), query, args, destination)
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}
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func QueryContext(statement Statement, db execution.DB, context context.Context, destination interface{}) error {
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func queryContext(statement Statement, db execution.DB, context context.Context, destination interface{}) error {
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query, args, err := statement.Sql()
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if err != nil {
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@ -58,7 +67,7 @@ func QueryContext(statement Statement, db execution.DB, context context.Context,
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return execution.Query(db, context, query, args, destination)
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}
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func Exec(statement Statement, db execution.DB) (res sql.Result, err error) {
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func exec(statement Statement, db execution.DB) (res sql.Result, err error) {
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query, args, err := statement.Sql()
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if err != nil {
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@ -68,7 +77,7 @@ func Exec(statement Statement, db execution.DB) (res sql.Result, err error) {
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return db.Exec(query, args...)
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}
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func ExecContext(statement Statement, db execution.DB, context context.Context) (res sql.Result, err error) {
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func execContext(statement Statement, db execution.DB, context context.Context) (res sql.Result, err error) {
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query, args, err := statement.Sql()
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if err != nil {
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@ -67,8 +67,12 @@ ORDER BY payment.payment_id ASC
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LIMIT 30;
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`
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query := SELECT(Payment.AllColumns, Customer.AllColumns).
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FROM(Payment.INNER_JOIN(Customer, Payment.CustomerID.EQ(Customer.CustomerID))).
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query := SELECT(
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Payment.AllColumns,
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Customer.AllColumns,
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).
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FROM(Payment.
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INNER_JOIN(Customer, Payment.CustomerID.EQ(Customer.CustomerID))).
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ORDER_BY(Payment.PaymentID.ASC()).
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LIMIT(30)
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@ -599,7 +603,9 @@ SELECT actor.actor_id AS "actor.actor_id",
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film_actor.actor_id AS "film_actor.actor_id",
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film_actor.film_id AS "film_actor.film_id",
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film_actor.last_update AS "film_actor.last_update",
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"rFilms"."film.title" AS "film.title"
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"rFilms"."film.film_id" AS "film.film_id",
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"rFilms"."film.title" AS "film.title",
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"rFilms"."film.rating" AS "film.rating"
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FROM dvds.actor
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INNER JOIN dvds.film_actor ON (actor.actor_id = film_actor.film_id)
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INNER JOIN (
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@ -621,7 +627,6 @@ FROM dvds.actor
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AsTable("rFilms")
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rFilmId := Film.FilmID.From(rRatingFilms)
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rTitle := Film.Title.From(rRatingFilms)
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query := Actor.
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INNER_JOIN(FilmActor, Actor.ActorID.EQ(FilmActor.FilmID)).
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@ -629,10 +634,10 @@ FROM dvds.actor
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SELECT(
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Actor.AllColumns,
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FilmActor.AllColumns,
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rTitle.AS("film.title"),
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rRatingFilms.AllColumns(),
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)
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fmt.Println(query.Sql())
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fmt.Println(query.DebugSql())
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assertStatementSql(t, query, expectedQuery)
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@ -136,21 +136,21 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
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}
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func (u *updateStatementImpl) DebugSql() (query string, err error) {
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return DebugSql(u)
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return debugSql(u)
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}
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func (u *updateStatementImpl) Query(db execution.DB, destination interface{}) error {
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return Query(u, db, destination)
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return query(u, db, destination)
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}
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func (u *updateStatementImpl) QueryContext(db execution.DB, context context.Context, destination interface{}) error {
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return QueryContext(u, db, context, destination)
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return queryContext(u, db, context, destination)
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}
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func (u *updateStatementImpl) Exec(db execution.DB) (res sql.Result, err error) {
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return Exec(u, db)
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return exec(u, db)
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}
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func (u *updateStatementImpl) ExecContext(db execution.DB, context context.Context) (res sql.Result, err error) {
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return ExecContext(u, db, context)
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return execContext(u, db, context)
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}
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@ -137,7 +137,7 @@ Following operators are only available on string expressions:
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| NOT_SIMILAR_TO | table.Film.Name.NOT_SIMILAR_TO(String("%Wind%")) | staff.active NOT SIMILAR TO %Wind% |
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## Cast operators
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## SQL Cast operators
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Cast operators allow expressions to be casted to some other database type.
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SQL builder expression type changes accordingly to database type.
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@ -158,4 +158,6 @@ SQL builder expression type changes accordingly to database type.
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| TO_TIMESTAMP | table.Film.Description.TO_TIMESTAMP() | film.description::timestamp |
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| TO_TIMESTAMPZ | table.Film.Description.TO_TIMESTAMPZ() | film.description::timestampz |
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## SQL builder cast
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TODO:
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248
wiki/SELECT.md
248
wiki/SELECT.md
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@ -0,0 +1,248 @@
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SELECT statement is used to retrieve records from one or more tables in PostgreSQL.
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More about SELECT statement in postgres can be found at: https://www.postgresql.org/docs/11/sql-select.html
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## SELECT statement clauses
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Following clauses are supported - SELECT, DISTINCT, FROM, WHERE, GROUP BY, HAVING, ORDER BY, LIMIT, OFFSET and FOR.
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_This list might be extended with feature Jet releases._
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##### 1. SELECT clause
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Sample SELECT clause written in Go:
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```
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jet.SELECT(
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jet.Int(1).ADD(jet.Int(12)).SUB(jet.Int(21)), // arbitrary expression
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table.Film.Name, // column
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table.Customer.FirstName.CONCAT(table.Customer.LastName).AS("FullName") // alias
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)
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```
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If jet and autogenerated table package, is dot "." imported, above statement will look more like native SQL:
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```
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SELECT(
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Int(1).ADD(Int(12)).SUB(Int(21)), // arbitrary expression
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Film.Name, // column
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Customer.FirstName.CONCAT(Customer.LastName).AS("FullName") // alias
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)
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```
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*For the most of the wiki dot import is used.*
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Above SQL clause written in go will produce following raw SQL:
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```
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SELECT 1 + 12 - 21,
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film.name AS "film.name", --
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customer.first_name || customer.last_name AS "FullName"
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```
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`film.name AS "film.name"` - column names are aliased by default. Alias is used during execution to map row result to
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appropriate `model` structure.
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##### 2. DISTINCT clause
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```
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SELECT(Film.Name).
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.DISTINCT().
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```
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Raw SQL:
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```
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SELECT DISTINCT film.name
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```
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##### 3. FROM clause
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```
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Go:
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1).FROM(Film)
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2).FROM(
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Film.
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INNER_JOIN(Language, Langauge.LanguageID.EQ(Film.FilmID))
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)
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SQL:
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1)FROM dvds.film
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2)FROM Film
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INNER JOIN Language ON (Language.LanguageID = Film.FilmID)
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```
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##### 4. WHERE clause
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```
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Go:
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.WHERE(Film.Length.GT(Int(150)))
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SQL:
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WHERE film.length > 150
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```
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##### 5. GROUP BY clause
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```
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Go:
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.GROUP_BY(Film.Length)
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SQL:
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GROUP BY film.length
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```
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##### 6. HAVING clause
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```
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Go:
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.HAVING(Film.Length.GT(Int(150))
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SQL:
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HAVING film.length > 150
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```
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##### 7. ORDER BY clause
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```
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Go:
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.ORDER_BY(Film.Length)
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SQL:
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ORDER BY film.length
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```
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##### 8. LIMIT clause
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```
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Go:
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.LIMIT(11)
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SQL:
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LIMIT 11
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```
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##### 9. OFFSET clause
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```
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Go:
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.OFFSET(11)
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SQL:
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OFFSET 11
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```
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##### 9. FOR clause
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```
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Go:
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.FOR(jet.NO_KEY_UPDATE)
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SQL:
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FOR NO KEY UPDATE
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```
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### Two forms of select statements in Jet
|
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#### 1. Classical select statement
|
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Columns selected are before tables selected
|
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```
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SELECT(
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Payment.AllColumns,
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Customer.AllColumns,
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).
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FROM(Payment.
|
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INNER_JOIN(Customer, Payment.CustomerID.EQ(Customer.CustomerID))).
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ORDER_BY(Payment.PaymentID.ASC()).
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LIMIT(30)
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```
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#### 2. Jet select statement
|
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Joined tables(or just one) are before columns selected. There is no FROM.
|
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```
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Payment.
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INNER_JOIN(Customer, Payment.CustomerID.EQ(Customer.CustomerID))
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SELECT(
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Payment.AllColumns,
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||||
Customer.AllColumns,
|
||||
).
|
||||
ORDER_BY(Payment.PaymentID.ASC()).
|
||||
LIMIT(30)
|
||||
```
|
||||
|
||||
Second form is added, because sometimes feels more natural to first think about the tables
|
||||
of interest, and than about the columns.
|
||||
**Both forms produces exactly the same raw SQL.**
|
||||
|
||||
## Sub-queries
|
||||
|
||||
How to write SELECT statement with sub-queries?
|
||||
|
||||
Sub-queries are composed first:
|
||||
```
|
||||
// select film_id and title from film table that have 'R' rating.
|
||||
rRatingFilms := Film.
|
||||
SELECT(
|
||||
Film.FilmID,
|
||||
Film.Title,
|
||||
).
|
||||
WHERE(Film.Rating.EQ(enum.MpaaRating.R)).
|
||||
AsTable("rFilms")
|
||||
```
|
||||
`AsTable("rFilms")` - allows SELECT statements to be seen as table.
|
||||
|
||||
To use sub-query columns in SELECT statement expressions we have to export column from sub-query,
|
||||
using `From` method.
|
||||
|
||||
```
|
||||
rFilmId := Film.FilmID.From(rRatingFilms) //used for join condition
|
||||
```
|
||||
|
||||
Now we can write:
|
||||
|
||||
```
|
||||
query := Actor.
|
||||
INNER_JOIN(FilmActor, Actor.ActorID.EQ(FilmActor.FilmID)).
|
||||
INNER_JOIN(rRatingFilms, FilmActor.FilmID.EQ(rFilmId)).
|
||||
SELECT(
|
||||
Actor.AllColumns,
|
||||
FilmActor.AllColumns,
|
||||
rRatingFilms.AllColumns(),
|
||||
)
|
||||
```
|
||||
`rRatingFilms.AllColumns(),` - sub-query columns needed for projection can be exported with AllColumns() method.
|
||||
No need to export each one of them with `From`.
|
||||
|
||||
Debug SQL of above example:
|
||||
```sql
|
||||
SELECT actor.actor_id AS "actor.actor_id",
|
||||
actor.first_name AS "actor.first_name",
|
||||
actor.last_name AS "actor.last_name",
|
||||
actor.last_update AS "actor.last_update",
|
||||
film_actor.actor_id AS "film_actor.actor_id",
|
||||
film_actor.film_id AS "film_actor.film_id",
|
||||
film_actor.last_update AS "film_actor.last_update",
|
||||
"rFilms"."film.film_id" AS "film.film_id",
|
||||
"rFilms"."film.title" AS "film.title",
|
||||
"rFilms"."film.rating" AS "film.rating"
|
||||
FROM dvds.actor
|
||||
INNER JOIN dvds.film_actor ON (actor.actor_id = film_actor.film_id)
|
||||
INNER JOIN (
|
||||
SELECT film.film_id AS "film.film_id",
|
||||
film.title AS "film.title",
|
||||
film.rating AS "film.rating"
|
||||
FROM dvds.film
|
||||
WHERE film.rating = 'R'
|
||||
) AS "rFilms" ON (film_actor.film_id = "rFilms"."film.film_id");
|
||||
```
|
||||
|
||||
|
||||
#### What If sub-query projection is not a column?
|
||||
For instance:
|
||||
```
|
||||
customersPayments := Payment.
|
||||
SELECT(
|
||||
Payment.CustomerID,
|
||||
SUMf(Payment.Amount).AS("amount_sum"),
|
||||
).
|
||||
GROUP_BY(Payment.CustomerID).
|
||||
AsTable("customer_payment_sum")
|
||||
|
||||
customerId := Payment.CustomerID.From(customersPayments)
|
||||
```
|
||||
|
||||
To export `"amount_sum"` from `customersPayments` sub-query we have to create column first with appropriate type and a name.
|
||||
Because SUMf produces float expression we will create FloatColumn with name of the column alias `"amount_sum"`
|
||||
```
|
||||
amountSum := FloatColumn("amount_sum").From(customersPayments)
|
||||
```
|
||||
35
wiki/Statements.md
Normal file
35
wiki/Statements.md
Normal file
|
|
@ -0,0 +1,35 @@
|
|||
|
||||
Following statements are supported:
|
||||
|
||||
* [SELECT](https://github.com/go-jet/jet/wiki/SELECT)
|
||||
* [INSERT](https://github.com/go-jet/jet/wiki/INSERT)
|
||||
* [UPDATE](https://github.com/go-jet/jet/wiki/UPDATE)
|
||||
* [DELETE](https://github.com/go-jet/jet/wiki/DELETE)
|
||||
* [LOCK](https://github.com/go-jet/jet/wiki/LOCK)
|
||||
|
||||
_This list might be extended with feature Jet releases._
|
||||
|
||||
There is a common set of action that can be performed for each statement type:
|
||||
|
||||
- `Sql() (query string, args []interface{}, err error)` - retrieves parametrized sql query with list of arguments
|
||||
- `DebugSql() (query string, err error)` - retrieves debug query where every parametrized placeholder is replaced with its argument.
|
||||
- `Query(db execution.DB, destination interface{}) error` - executes statements over database connection db and stores row result in destination.
|
||||
- `QueryContext(db execution.DB, context context.Context, destination interface{}) error` - executes statement with a context over database connection db and stores row result in destination.
|
||||
- `Exec(db execution.DB) (sql.Result, error)` - executes statement over db connection without returning any rows.
|
||||
- `ExecContext(db execution.DB, context context.Context) (sql.Result, error)` - executes statement with context over db connection without returning any rows.
|
||||
|
||||
Database connection can be of any type that implements following interface:
|
||||
|
||||
```go
|
||||
type DB interface {
|
||||
Exec(query string, args ...interface{}) (sql.Result, error)
|
||||
ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error)
|
||||
Query(query string, args ...interface{}) (*sql.Rows, error)
|
||||
QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)
|
||||
}
|
||||
```
|
||||
|
||||
These include but are not limited to:
|
||||
- `sql.DB`
|
||||
- `sql.Tx`
|
||||
- `sql.Conn`
|
||||
|
|
@ -3,9 +3,9 @@
|
|||
* [Generator](https://github.com/go-jet/jet/wiki/Generator)
|
||||
* [Writing SQL in Go]()
|
||||
* [Expressions](https://github.com/go-jet/jet/wiki/Expressions)
|
||||
* [Statements]()
|
||||
* [SELECT]()
|
||||
* [INSERT]()
|
||||
* [UPDATE]()
|
||||
* [DELETE]()
|
||||
* [LOCK]()
|
||||
* [Statements](https://github.com/go-jet/jet/wiki/Statements)
|
||||
* [SELECT](https://github.com/go-jet/jet/wiki/SELECT)
|
||||
* [INSERT](https://github.com/go-jet/jet/wiki/INSERT)
|
||||
* [UPDATE](https://github.com/go-jet/jet/wiki/UPDATE)
|
||||
* [DELETE](https://github.com/go-jet/jet/wiki/DELETE)
|
||||
* [LOCK](https://github.com/go-jet/jet/wiki/LOCK)
|
||||
Loading…
Add table
Add a link
Reference in a new issue