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 Go to latest Published: Sep 25, 2017 License: MIT Imports: 13 Imported by: 0

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Constants

View Source 
const (
	DefaultDBName = "justsql"
)

Variables

This section is empty.

Functions

This section is empty.

Types

type ColumnMeta 

type ColumnMeta struct {
	*model.ColumnInfo

	Table *TableMeta

	Name       string
	PascalName string

	Offset int

	// Column field type.
	Type *types.FieldType
}

ColumnMeta contains meta data of a column.

func NewColumnMeta 

func NewColumnMeta(ctx *Context, tableMeta *TableMeta, columnInfo *model.ColumnInfo) (*ColumnMeta, error)

func (*ColumnMeta) DefaultValue 

func (c *ColumnMeta) DefaultValue() interface{}

func (*ColumnMeta) Elems 

func (c *ColumnMeta) Elems() []string

func (*ColumnMeta) IsAutoInc 

func (c *ColumnMeta) IsAutoInc() bool

func (*ColumnMeta) IsEnum 

func (c *ColumnMeta) IsEnum() bool

func (*ColumnMeta) IsNotNULL 

func (c *ColumnMeta) IsNotNULL() bool

func (*ColumnMeta) IsOnUpdateNow 

func (c *ColumnMeta) IsOnUpdateNow() bool

func (*ColumnMeta) IsSet 

func (c *ColumnMeta) IsSet() bool

type Context 

type Context struct {
	// The embeded db.
	DB *EmbedDB

	// Default database name in embeded db.
	DBName string

	// Database name -> cached DBMeta
	CachedDBMeta map[string]*DBMeta
}

Context contains an embeded database (tidb), extracted database meta information.

func NewContext 

func NewContext(storePath, dbName string) (*Context, error)

NewContext create new Context.

func (*Context) ClearCachedDBMeta 

func (ctx *Context) ClearCachedDBMeta()

ClearCachedDBMeta clears all cached DBMeta.

func (*Context) GetDBMeta 

func (ctx *Context) GetDBMeta(dbName string) (*DBMeta, error)

GetDBMeta get DBMeta of the given db name or use cached one.

func (*Context) UniqueTableName 

func (ctx *Context) UniqueTableName(dbName, tableName string) string

UniqueTableName == github.com/pingcap/tidb/plan/resolver.go nameResolver.tableUniqueName

type DBMeta 

type DBMeta struct {
	*model.DBInfo

	Name       string
	PascalName string

	Tables map[string]*TableMeta
}

DBMeta contains meta information of a database.

func NewDBMeta 

func NewDBMeta(ctx *Context, dbInfo *model.DBInfo) (*DBMeta, error)

type DeleteStmtMeta 

type DeleteStmtMeta struct {
	*ast.DeleteStmt
}

DeleteStmtMeta contains meta information of a DELETE statement.

func NewDeleteStmtMeta 

func NewDeleteStmtMeta(ctx *Context, stmt *ast.DeleteStmt) (*DeleteStmtMeta, error)

NewDeleteStmtMeta create DeleteStmtMeta from *ast.DeleteStmt.

type EmbedDB 

type EmbedDB struct {
	Store kv.Storage
	Sess  tidb.Session
}

Use TiDB as an embeded database to execute or parse SQLs.

func NewEmbedDB 

func NewEmbedDB(storePath string) (*EmbedDB, error)

func (*EmbedDB) Compile 

func (db *EmbedDB) Compile(stmt ast.StmtNode) (ast.Statement, error)

Compile stmt.

func (*EmbedDB) Ctx 

func (db *EmbedDB) Ctx() context.Context

DB context.

func (*EmbedDB) Domain 

func (db *EmbedDB) Domain() *domain.Domain

Get Tidb domain (storage space).

func (*EmbedDB) Execute 

func (db *EmbedDB) Execute(src string) ([]ast.RecordSet, error)

Execute some SQLs.

func (*EmbedDB) MustExecute 

func (db *EmbedDB) MustExecute(src string)

Execute some SQLs and Panic if error.

func (*EmbedDB) Parse 

func (db *EmbedDB) Parse(src string) ([]ast.StmtNode, error)

Parse SQLs.

type FKMeta 

type FKMeta struct {
	*model.FKInfo

	Table *TableMeta

	Name       string
	PascalName string

	ColNames     []string
	RefTableName string
	RefColNames  []string
}

FKMeta contains meta data of a foreign key.

func NewFKMeta 

func NewFKMeta(ctx *Context, tableMeta *TableMeta, fkInfo *model.FKInfo) (*FKMeta, error)

func (*FKMeta) Columns 

func (f *FKMeta) Columns() []*ColumnMeta

func (*FKMeta) RefColumns 

func (f *FKMeta) RefColumns() []*ColumnMeta

func (*FKMeta) RefIndex 

func (f *FKMeta) RefIndex() *IndexMeta

RefIndex find the first index in ref table that this foreign key use.

func (*FKMeta) RefTable 

func (f *FKMeta) RefTable() *TableMeta

type FieldListMeta 

type FieldListMeta struct {
	// Wildcard information.
	Wildcards []WildcardMeta

	// Map index of result field -> index in wildcards or -1 if the result field
	// is not in a wildcard.
	ResultFieldToWildcard []int
}

FieldListMeta contain field list meta information in SELECT statement.

func NewFieldListMeta 

func NewFieldListMeta(ctx *Context, stmt *ast.SelectStmt, tableRefsMeta *TableRefsMeta) (*FieldListMeta, error)

NewFieldListMeta create FieldListMeta from the field list and table refs of a SELECT statement.

func (*FieldListMeta) WildcardColumnOffset 

func (f *FieldListMeta) WildcardColumnOffset(i int) int

WildcardColumnOffset return the offset inside wildcard of the i-th result field or -1 if the result field is not inside wildcard.

func (*FieldListMeta) WildcardTableRefName 

func (f *FieldListMeta) WildcardTableRefName(i int) string

WildcardTableRefName return the wildcard table ref name of the i-th result field or "" if the result field is not inside wildcard.

type IndexMeta 

type IndexMeta struct {
	// Nil if it is created from PKHandler.
	*model.IndexInfo

	Table *TableMeta

	Name       string
	PascalName string

	Unique        bool
	Primary       bool
	ColumnIndices []int
}

IndexMeta contains meta data of an index.

func NewIndexMeta 

func NewIndexMeta(ctx *Context, tableMeta *TableMeta, indexInfo *model.IndexInfo) (*IndexMeta, error)

func NewIndexMetaFromPKHandler 

func NewIndexMetaFromPKHandler(ctx *Context, tableMeta *TableMeta) *IndexMeta

see: https://github.com/pingcap/tidb/issues/3746

func (*IndexMeta) Columns 

func (i *IndexMeta) Columns() []*ColumnMeta

type InsertStmtMeta 

type InsertStmtMeta struct {
	*ast.InsertStmt
}

InsertStmtMeta contains meta information of a INSERT statement.

func NewInsertStmtMeta 

func NewInsertStmtMeta(ctx *Context, stmt *ast.InsertStmt) (*InsertStmtMeta, error)

NewInsertStmtMeta create InsertStmtMeta from *ast.InsertStmt.

type ResultFieldMeta 

type ResultFieldMeta struct {
	*ast.ResultField

	// Field name, maybe contain non-identifier chars: "now()"
	Name string

	// Field type.
	Type *types.FieldType
}

ResultFieldMeta contains meta information of a result field.

func NewResultFieldMeta 

func NewResultFieldMeta(ctx *Context, rf *ast.ResultField) (*ResultFieldMeta, error)

func (*ResultFieldMeta) Elems 

func (rf *ResultFieldMeta) Elems() []string

func (*ResultFieldMeta) IsAutoInc 

func (rf *ResultFieldMeta) IsAutoInc() bool

func (*ResultFieldMeta) IsEnum 

func (rf *ResultFieldMeta) IsEnum() bool

func (*ResultFieldMeta) IsNotNULL 

func (rf *ResultFieldMeta) IsNotNULL() bool

func (*ResultFieldMeta) IsOnUpdateNow 

func (rf *ResultFieldMeta) IsOnUpdateNow() bool

func (*ResultFieldMeta) IsSet 

func (rf *ResultFieldMeta) IsSet() bool

type SelectStmtMeta 

type SelectStmtMeta struct {
	*ast.SelectStmt

	ResultFields []*ResultFieldMeta
	TableRefs    *TableRefsMeta
	FieldList    *FieldListMeta
}

SelectStmtMeta contains meta information of a SELECT statement.

func NewSelectStmtMeta 

func NewSelectStmtMeta(ctx *Context, stmt *ast.SelectStmt) (*SelectStmtMeta, error)

NewSelectStmtMeta create SelectStmtMeta from *ast.SelectStmt.

func (*SelectStmtMeta) ExpandWildcard 

func (s *SelectStmtMeta) ExpandWildcard(ctx *Context) (*SelectStmtMeta, error)

This function expand all wildcards ("*") in a SELECT statement and return a new equivalent one. This is useful since "SELECT * ..." may lead to unpredictable error when table is altered.

type TableMeta 

type TableMeta struct {
	*model.TableInfo

	DB *DBMeta

	Name       string
	PascalName string

	Columns     []*ColumnMeta
	Indices     []*IndexMeta
	ForeignKeys []*FKMeta
	// contains filtered or unexported fields
}

TableMeta contains meta information of a table.

func NewTableMeta 

func NewTableMeta(ctx *Context, dbMeta *DBMeta, tableInfo *model.TableInfo) (*TableMeta, error)

func (*TableMeta) AutoIncColumn 

func (t *TableMeta) AutoIncColumn() *ColumnMeta

Return auto increment column if exists.

func (*TableMeta) ColumnByName 

func (t *TableMeta) ColumnByName(name string) *ColumnMeta

Retrive column by its name.

func (*TableMeta) NonPrimaryColumns 

func (t *TableMeta) NonPrimaryColumns() []*ColumnMeta

Return non-primary columns if exists.

func (*TableMeta) PrimaryColumns 

func (t *TableMeta) PrimaryColumns() []*ColumnMeta

Return primary key columns if exists.

type TableRefsMeta 

type TableRefsMeta struct {
	// List of table sources and its reference name. Reference name can be the following:
	//   - tbl_name
	//   - other_database.tbl_name
	//   - alias
	TableSources  []*ast.TableSource
	TableRefNames []string

	// Not nil if TableSources[i] is normal table.
	TableMetas []*TableMeta

	// Map table ref name to its index.
	// Similar to github.com/tidb/plan/resolver.go:resolverContext,
	// but only use one map to enforce name uniqueness for both normal tables and derived tables.
	TableRefNameMap map[string]int
}

TableRefsMeta contains meta information of table references (e.g. 'FROM' part of SELECT statement).

CASE 1: 

MySQL allows a normal table and a derived table sharing a same name:
   "SELECT a.* FROM t AS a JOIN (SELECT 1) AS a;"
 "a.*" expands to all columns of the two tables.
 Also see comments of github.com/pingcap/tidb/plan/resolver.go:handleTableSource

CASE 2: 

"SELECT user.* FROM user, mysql.user" is also allowed, "user.*" also expands to all
columns of the two tables. This may lead to confusion.

Due to the reasons above, JustSQL enforce table referernce names' uniqueness, even in different database ("mysql.user" and "user"). Thus the above SQLs should modified to something like: 

"SELECT a1.*, a2.* FROM t AS a1 JOIN (SELECT 1) AS a2;
"SELECT u1.*, u2.* FROM user u1, mysql.user u2"

func NewTableRefsMeta 

func NewTableRefsMeta(ctx *Context, refs *ast.TableRefsClause) (*TableRefsMeta, error)

func (*TableRefsMeta) GetResultFields 

func (t *TableRefsMeta) GetResultFields(tableRefName string) []*ast.ResultField

GetResultFields return a list of result field of the table or nil if not exists.

func (*TableRefsMeta) TableMeta 

func (t *TableRefsMeta) TableMeta(tableRefName string) *TableMeta

TableMeta return *TableMeta if tableRefName references a normal table or nil if tableRefName references a derived table.

type UpdateStmtMeta 

type UpdateStmtMeta struct {
	*ast.UpdateStmt
}

UpdateStmtMeta contains meta information of a UPDATE statement.

func NewUpdateStmtMeta 

func NewUpdateStmtMeta(ctx *Context, stmt *ast.UpdateStmt) (*UpdateStmtMeta, error)

NewUpdateStmtMeta create UpdateStmtMeta from *ast.UpdateStmt.

type WildcardMeta 

type WildcardMeta struct {
	// Table ref name of wildcard.
	TableRefName string

	// Portion of the wildcard in result fields.
	ResultFieldOffset int
	ResultFieldNum    int
}

WildcardMeta contain information for a wildcard. NOTE: For unqualified wildcard "*", serveral WildcardMeta will be generated.

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