Python Pandas - Selecting multiple rows in Pandas DataFrame

Query selection

 df.query("field_name == 'value'")
 df.query("field_name == 'value1' & field_name2 == 'value2'")

Multi selection

 df[df['field_name'] == 'value']
 df[df['field_name'] == 'value1'][df['field_name'] == 'value2']
 df[(df['field_name'] == 'value1') & (df['field_name2'] == 'value2')]

.loc selection

Selecting some rows and all columns 

 df.loc[df['field_name'] == 'value', :]

Selecting some rows and some columns

 df.loc[df['field_name'] == 'value', ['field_name','field_name2']]

Multi selection

 df.loc[(df['field1'] == 'value1') & (df['field2'] == 'value2'), ['field_name','field_name2']]

Regexp selection

 df.loc[df['field'].str.contains('REGEXP EXPRESSION'),:]
 df.loc[df['numeric_field'].astype(str).str.contains('REGEXP EXPRESSION'),:]

isin selection

 df[df['field'].isin(['value1','value2'])]
 df[df['field'].isin({'field1':['value1']}, {'field2':['value2']})]